How Competitive Skill Rating Works (Season 9)

The rating and matchmaking system is confusing, and a good overview does not appear to be available. The official overview (1) is incomplete and does not answer a number of common player questions and concerns. This information below is gathered from sporadic blue posts and developer update videos, and salted with my own experience and experiments, various forum threads, and watching streams. Note that since Blizzard does not give exact algorithms, I do have to fill in some gaps, or leave some items unknown. I will edit this post as information becomes available, or the SR system changes.

Whenever you see a number in parenthesis, look to the references section and follow the link to see the support for the statement in question.


See the later sections for a more in-depth exposition, as well as references to supporting material.

How do I maximize my Skill Rating?

In order:
1) Win games
2) If diamond or above, play a minimum of 4.67 games per week (starting one week after placements).
3) If platinum or below, perform well, statistics-wise, with the chosen hero.

In my last game, my Skill Rating went up/down by X. Why did this happen?

The details of Skill Rating (SR) movement in a match depends on whether a player wins or loses, the Match-making-rating (MMR) mismatch between the two teams, the mismatch between the player’s SR and MMR, whether a player is new, whether a player is active, the player’s statistical performance, the player’s position on the ladder, and possible bugs. Add it all together and it is nearly impossible to determine why a player’s SR has a specific movement in a particular match. Sometimes over the course of twenty to one hundred matches it can be seen that one particular cause is dominant, but that often depends on careful data collection and some guesswork.

Summarize matchmaking, rating, and progression for me

MMR is a (hidden) number that goes up when you win, and down when you lose. How much it goes up and down is a complicated formula, based on many factors, but the essential truth of wins are good and losses are bad is certain (4).

That MMR is then used to match people with and against people of similar MMR, in an attempt to create a 50% match (32). Here is the key part:

If a player’s MMR is wrong and too low, then the odds to win will be greater than 50%, and the player will win more games than he loses, which will cause his MMR to rise over many games played. He will then be placed with stronger and stronger opponents (and stronger and stronger allies) until his MMR is correct, and his win percentage approaches 50% (with some random oscillation around 50%) (7).

Once a player finds himself trapped in a rating range, the only way to break out is to improve as a player and play enough games to overcome any random factors (47).

What is SR then? SR is a visible and friendlier approximation of MMR (23). It has no more meaning with respect to matchmaking than tier icons. However, except for top players who have decayed, MMR and SR are closely linked, so inspecting SR typically gives a reasonable estimate of a player’s MMR (23).

< 500 Bronze, SR not listed
500-1499 Bronze
1500-1999 Silver
2000-2499 Gold
2500-2999 Platinum
3000-3499 Diamond
3500-3999 Master
4000-5000 Grandmaster
Top 500 players in region.

For season 3, the rank distribution was Bronze: 6%, Silver: 22%, Gold: 34%, Platinum: 23%, Diamond: 10%, Master: 3%, Grandmaster: <1% (3). For season 8, the rank distribution was Bronze: 8%, Silver: 21%, Gold: 32%, Platinum: 25%, Diamond: 10%, Master: 3%, Grandmaster: 1% (6). Third-party sites such as masteroverwatch do not give reliable distributions because players have to actually log in to those sites for it to count the data. This skews those sites heavily toward higher ranked players.

As a player gains SR, he will be promoted to the next tier when appropriate. He will drop out of each tier as he loses rank. However, there is some loss protection for Diamond and below. After a loss (but not a win), the game will check to see what a player’s current tier and skill rating are. If his skill rating has not exceeded the minimum for his current tier for the past five games, he will be demoted (16). For Master and Grandmaster, a player will be demoted immediately if his skill rating is not high enough. Competitive point rewards are based on the highest rank achieved during the season (16). Ranks and SR are wiped each season (but not MMR, see below).

The top 500 leaderboard becomes available two weeks after season start. To be eligible, a player must have played at least 50 games that season (45), all from one region. However, there were several past seasons where the 50 game restriction was not enforced. For example, there was a player who finished in top 500 with only 17 games (Season 6, Americas, rank 498, in-game leaderboard). This appears to have been a bug that was silently created and fixed. The top 500 spray and icon are not awarded unless a player is in top 500 at the end of the season (18).


Matchmaking is based on hidden match-making-rating (MMR), not skill-rating (SR) (3, 21, 25, 40). Competitive MMR is separate from the MMR of other modes (37).

The game uses MMR to determine whether a match is fair, and attempts to match teams such that the game is fair (each team has a 50% chance of winning) (32). Upon victory, the winners receive a bump up in SR and MMR, and the losers get bumped down. At times (off peak-hours or very high/low rated players), finding a fair match will be impossible in a reasonable amount of time, and the match maker will match teams based on a best fit. However, note that if only very imbalanced matches are available (the infamous Brazilian six stack playing at 3 AM), then no match will be made and queue times will become extreme to infinite (3). The tuning for what is very imbalanced is a number that is not published and can change with time. In the middle ground, top (or bottom) players will have a longer, but not infinite queue, to attempt to find a better match (15).

If the match making algorithm determined before the game that it was not fair, the higher ranked team will receive less SR/MMR on a win, and lose more SR/MMR on a loss. The lower ranked team will receive more SR/MMR on a win, and lose less SR/MMR on a loss (2). This is standard for Elo (rating system from chess) type systems. Draws cause no change in SR and have an unknown effect on MMR.

In addition to MMR, the match maker attempts to match on ping and group size (32) and to make matches reasonably quickly. (Jeff also mentions quarantining new players from the general population, but this effect does not apply to competitive).

If the matchmaker has difficulty finding groups of equal size, it will give a small advantage in MMR to the team of solo-queue players to counter-act the synergy advantage of the group, and to keep the match having a predicted win percentage of 50% (2). It makes similar modifications when matching three-stacks against two-stacks, etc. This has an unfortunate side effect that if a player groups with someone with whom they have poor synergy, it acts as a penalty on their practical win likelihood. A similar problem can occur when players use the stay-as-team button and are matched against teams with more experience together. Finally, large groups tend to have longer queue times while the matchmaker tries to find other large groups. I refer to all these effects as the stacking penalty, and is an area where the matchmaker could use some improvement.

If the match-maker says most games are fair, then why are there so many stomps?

There are many reasons:

  1. Overwatch, as a game, has a tendency to snowball. The winner of the first fight has an ultimate advantage that has a tendency to last the round. Losing teams tend to tilt and start playing poorly, which can continue in the same round and carry into the next round.

  2. Random variables are random. Maybe a cat walked on a keyboard or someone fat fingered an ult (7). Maybe someone who has 99% up-time for their internet had their 1% failure that day. Maybe one team has all dps mains, and the other team is well balanced. MMR and predicted win percentage only has validity over many matches, not each individual match.

  3. Not every player tries hard every match. Sometimes this is subtle, like playing with a beer or two too many. Sometimes it is less subtle, like practicing a hero a player is not good at, regardless of team comp or map.

  4. Some players actively break the system, by either hard throwing, that is intentionally losing (as opposed to soft throwing as in item 3), playing on someone else’s account to boost it, or other similar actions. These actions are bannable and should be reported when seen. Blizzard has promised to take stronger actions against this sort of thing (17). However, soft throwers and hard throwers can be difficult to distinguish, and Blizzard has to error on the side of caution to avoid banning the wrong people, so it will always be a problem. The in-game report UI, as well as a key blue post (36), give guidelines on what behavior is or is not bannable.

  5. New accounts in general have less data and will have a less accurate MMR. There is no required minimum number of games to play, so new accounts can stay “new” for a very long time.

  6. MMR itself is only approximate. See the section on “How Accurate is SR”, below and realize that MMR generally will have the same issues as SR, with respect to accuracy, except it is harder to measure what is going on with MMR.

Okay, stomps are going to happen, but why are there so many win/loss streaks and large SR/MMR movements? Shouldn’t a player’s SR/MMR be fairly stable once he gets to the proper rank?

Win probability changes slowly with rank because there are so many random factors in each individual match. Unfortunately, it follows from this that frequent and long streaks will occur, and a player’s rank will oscillate widely. Essentially, a player will tend to bounce between the range of where he is nearly guaranteed to win and where he is nearly guaranteed to lose. The range varies from player to player, but +/- 250 SR/MMR is common and +/- 500 is possible. This problem can be analyzed in depth, mathematically (34).

Skill Rating

Skill Rating (SR) should be thought of as a visible and friendlier approximation of MMR, similar to tier icons. With the exception of diamond+ players who have decayed (see below), MMR and SR are closely linked (22). The SR/MMR convergence is implemented by having each match pull SR in the direction of MMR. That is, if SR is lower than MMR, a player will win more SR than MMR on a win, and lose less SR than MMR on a loss. When I refer to an SR buff, this is how the buff is implemented (14).

There is indirect evidence (see the “Season Transitions” section, below) that average MMR movement for established accounts is 19.0. For active and established accounts, typical SR movement is 20-30. If an account is inactive for a while, after the player returns SR/MMR gains will be exaggerated again for a time (2). For this reason, players that only do placements each season will tend to see high volatility in their rating each season.

In addition to Elo type effects for high rated players (in which they gain less SR/MMR because there are no fair matches available), there is an extra SR debuff for high ranked players to prevent them from getting to the SR limit of 5000. The concern here is that players would start to pile up at the limit of 5000 and break the leaderboard (35).

New accounts

If a player has never played competitive, his initial competitive SR is around 2350 (38). For new players, MMR and SR are more volatile (35) and SR has been measured to approximately follow the formula: SR change = -3.85 * game + 99.34 (38) until about game 18. So even though everyone starts around 2350, after 18 matches, there is a wide variation in ratings. To fall to the depths of bronze, or climb the highs of top 500, requires significantly more games, however. That is, newer accounts tend to be artificially close to high gold.

If MMR are SR are so similar, why have both? Isn’t that unnecessarily confusing? Can’t we handle the problem of rank camping (see below) some other way?

In a word, yes. Here I’m going to engage in editorializing and reading between the lines of the blue posts. See this as my informed, but unverified, opinion. The real purpose of MMR is to provide Blizzard’s absolute best estimate of each player’s ability. However, since it is invisible to the players, Blizzard can change how it is calculated at any time and can have movements or changes that feel bad (23). SR, on the other hand, is player facing, and subject to player psychology. Aside from players’ tendency to over-react to every little thing, blizzard uses SR to influence player behavior (SR buff at the beginning of the season (now removed), SR penalty for leaving, SR penalty for being inactive) and to coddle players’ tender egos (23).

The good news is that as Blizzard is getting more confidence in the system, goofiness like this is slowly getting removed. Streak bonuses were removed. The knock down / build up in SR at the beginning of the season was removed. Performance modifiers are being dialed down. There may be some day in the future when Blizzard has enough confidence in MMR to make it public, and to abolish SR. I propose that we deal with the problem of rank camping by having tier decay (top 500 → grandmaster → master → diamond) but not SR/MMR decay.

High win percentage debuff / Low win percentage buff

As mentioned, SR is pulled in the direction of MMR (22). There is evidence (29) that this leads to an unfortunate and unintended side effect: If SR is well above MMR because a player has won many more games than he’s lost, less SR than MMR will be gained on a win, and more SR than MMR will be lost on a loss. This is an SR debuff. At high win percentage, a player can gain up to 6 SR less on a win than he loses on a loss (29). The effect is expected to reverse at low win percentage (SR would be buffed). The effect goes away once a player’s win percentage gets near 50%. That is, the player’s MMR is not ruined for life.

Rank Decay

To prevent rank camping, for players ranked 3000 SR or higher, their rank will decay 25 SR per day if they do not play. Each game a player plays increases his buffer by 36 hours, to a maximum of one week (20). Each day a player’s decay buffer decreases by 24 hours. If it hits zero, decay starts. To determine how many games must be played per week to avoid decay, we can calculate (1 game / 36 hours) * (168 hours / week) = 4.67 games / week. This is slightly lower than the 5 games per week that was originally reported (15). To see if decay is imminent look on the right hand side of the information screen of the competitive play card. After returning from decay, the player will have a substantial SR buff (gain more SR from wins than he loses from loses) until he is back where he was (3). While decayed, a player’s MMR (and hence matchmaking) does not change (3). The decay clock doesn’t start until the player does his placement matches.

Performance Modifier

In platinum and below, SR/MMR gains are adjusted up or down based on the performance of the player. This is a minor factor (2). This is done based on a numerical comparison of measureable quantities such as elims, deaths, assists, damage blocks, ults cast, etc. between a given player and other players of that hero at that MMR (8). Generally it is assumed that the measured stats are those visible to the player, but that has never been confirmed by Blizzard. Most of the details of this implementation are fuzzy and not published (probably to reduce exploits). This performance measure is correlated but not identical to “on fire” calculations. “On fire” compares a player to his teammates, while SR/MMR bonuses compare a player to other players that are not in the current match, but in a similar skill bracket, and playing the same hero (8). The effect of the performance modifier is generally small, but there are plausible reports of it causing people to have to maintain a 55%+ win rate to maintain their SR (11).

This is the most controversial (among many controversies) part of the SR system. There are two camps, those who don’t want their SR/MMR to be so heavily influenced by those in their group, and those who worry that having a performance based system will cause people to not play the objectives / win conditions and instead go stat hunting. In addition to people who go stat hunting, people can unintentionally be at the wrong rank because their good / bad play is not reflected in their stats. In the early days, these groups were roughly equal, but lately those advocating for no performance modifier are more numerous.

Starting in season 8 (January 2018), the performance modifier was removed for diamond and above (35). Blizzard has started to realize that having a motivation other than winning causes all sorts of non-ideal behavior and effects. The immediate forum response has been to request this change for lower tiers as well (at least whatever tier the poster happens to be in). However performance modifiers do help move new players where they belong much faster than an Elo type system, so I propose that the performance modifier be removed for Bronze to Platinum players after a sufficient number of competitive games has been played. Blizzard can use their data to determine how long it takes for people for their rank to stabilize, which would be a good place for a cutoff.

Season Transitions

Players’ 10 placement matches will start with Blizzard’s best estimate of each player’s MMR for matchmaking purposes (15). A player’s initial SR will generally be close to his previous season ending SR, with a relatively ordinary adjustment based on 10 placement matches.

However, occasionally a player will have a large movement (24) in either direction. This happens on relatively inactive accounts (39), and can be explained by Scott’s statement: “Play a lot of games, it (MMR) gets more certain. Don’t play Overwatch for a while, it gets less certain. The more certain the matchmaker is about your MMR, the less your MMR will change in either direction based on a win or loss” (2). Essentially, if a player only does his placements, or slightly more than that, in a season, his MMR/SR is prone to much wider swings when he returns.

Because of reasonably high quality data for seasons 6, 7, 8, and 9 (24), it is possible to derive a formula: (New Season Starting SR) = (-173.7 +/- 20.8) + (1.0015 +/- .0059) * (Previous season Ending SR) + (37.94 +/- 2.23) * (Placement Wins). New Season Starting SR has a standard error of 181 SR (24), which implies a possible change in rating during placements of +/- 500 SR for inactive accounts. For active accounts, the max range is more like +/- 200 (from winning or losing all matches).

Decay does not persist through season transitions. That is, if a player decays from 4000 to 3000 before the season break, he will typically place around 4000 after the season break. Of course, if he is an inactive player (which decayed players often are), he may see an unexpectedly large swing in either direction.

Prior to season 6 (September 2017), players’ SR would be bumped down below their MMR at the beginning of the season, and they would earn it back with an SR buff over the course of 50 matches. This felt bad and was removed (15).

As an aside, it is possible from this data to derive the typical movement in MMR. It is safe to assume that the average SR of the entire community matches the average MMR of the entire community at the end of the season. It is also likely that the SR matches MMR exactly after placements. In theory, decayed players would mess with this, but they are not common in the data and decay likely persists through season breaks so would not affect the analysis here. Overall, during placements, movement of SR and MMR is the same. With each additional win (as opposed to a loss), a player gains 19.0 SR / MMR. This effectively means that a player will win 19.0 MMR on a win, and lose 19.0 MMR on a loss. This typical MMR movement likely continues for the whole season, not just placements, while SR movement is more typically 20 - 30. This matches our evidence from elsewhere (how SR buffs work, high win percentage debuff) that MMR moves slower than SR.

How Accurate is SR?

On the forums there are generally two factions with respect to SR, those who think that SR is essentially luck and a meaningless value, and those who believe that SR is essentially correct. Neither of these factions have the correct approach. The correct question is to ask how accurate is SR? Clearly top 500 players are better than bottom 500 (see any bronze to GM series or watch low bronze play vs top play), so SR is not completely random, but how accurate is it really? For this discussion, I am assuming that we are talking about a player that plays to win every game, doesn’t share his account, and has played at least 100 competitive games, and continues to be an active player.

There are number of ways to approach this question. One is to start a completely new account, and then play 100 games on the new account and see how it performs compared to the old one. This shows that SR can vary by 1000 SR in extreme cases, and 500 in normal cases (27). There is some evidence that reroll experiments show less variance at higher ranks (28) likely because there are less random variables, such as smurfs, throwers, and inconsistent play.

Next, any player can see how his SR changes during a season. A range of 500 is completely normal here.

In addition, if an account needs a 55% win rate to maintain SR (11), and if win % changes slowly with rank, then it is expected that this will be an additional source of significant error in SR.

If a player gets noticeably better, it can take a long time to get to the correct rank. If a player maintains a 55% win rate, he will only go up approximately 220 SR/MMR every 100 games. Because there are twelve players in a match, one player’s contribution (and ability to carry the match) is limited unless he is playing at a vastly different skill level, so a 55% win rate for a player that is moderately under placed is to be expected.

Put this all together, and we can state that an active and motivated player’s SR is only accurate to +/- 250 SR in normal circumstances and +/- 500 SR in extreme cases. Of course, new players, barely active players, or players that actively break the system can be off by much more.

MMR/SR Reset

Periodically, there are calls on the forums for all MMR/SR information to be wiped and to start over. The justification here is that because the system has had many flaws, and that MMR/SR takes a very large number of games to move, and that people are misplaced by 250 to 500 SR (see previous section), that it would be good to wipe everything and start over. The chief problem with this is that before the wipe, the typical error is +/- 250 SR, with +/- 500 SR in extreme cases. Immediately after the wipe, the typical error would be +/- 2500, as everyone would have the same rating. Top 500 would be playing against bottom 500. This would cause matchmaking and rating quality to fall through the floor until a sufficient number of games are played. And because many people do not play a huge number of games, or play inconsistently, this inaccuracy would persist for months. And at the end of that, the accuracy would be similar to what it was before the reset, because the underlying system has not changed. My reasoning against a reset is similar to that given by Scott (12).

Popular Myths

There is a lot of repetition in these subsections. My apologies, but the various myths tend to have a lot of overlap. They also have incompatibilities, so it is difficult to address them except individually, with repetition.

SR is taken into account in matchmaking
I’ve already referenced all the posts indicating that indicate that matchmaking is done by MMR alone (3, 21, 25, 40). However, there are also three posts that indicate or imply that matchmaking is either based on SR or matchmaking is limited to a given SR range (5, 7, 35). Scott Mercer is the author of two of the yes SR posts, as well as one of the no SR posts, so he contradicts himself. The contradiction must be resolved somehow, and I decide in favor of SR being used in no way during matchmaking for the following reasons:

  1. Whenever MMR and SR are discussed in the same post (including by Scott), it is to say that SR is not used in matchmaking.
  2. Master+ players regularly see decayed “diamond” players in their matches. And when someone like Seagull decays down to diamond on stream, he is still placed in grandmaster / top 500 matches. If SR was either used for matching, or the limits on matching were restricted by SR, this should not happen.
  3. SR and MMR are closely linked (22), except for decayed players (who only exist in diamond+) so saying matching is done on one or the other is a distinction without much of a difference. This makes Scott being sloppy with the terms not as surprising and makes the answer to this question less important.
  4. There hasn’t been any clear revoking of the old system on this point so the belief that we should only keep the newest non-contradictory statement (35) is implausible.
  5. Generally the people who are insistent that SR and MMR are both used in matchmaking are using it to infer some broken or rigged system with horrible and implausible outcomes that are contradicted by careful analysis, common sense, and unrelated blue posts.

Forced loss streaks

There is an old and persistent conspiracy theory that Blizzard’s algorithms force players to have a 50% win rate by nefarious means (if a player is doing well, very poor players are put on his team to make him lose, often for many games in a row). This has been contradicted by Blizzard (7, 46), is contradicted by people’s ability to climb (13), and would be a horrible and difficult-to-implement design. The truth is much simpler. If a player wins more than he loses, his SR/MMR goes up. As it rises, he is placed against stronger opponents (and with stronger allies), which increases the chance that he will lose (7). Once in equilibrium, the average person he faces (and is allied with) is at his skill level, and the only way to go up is to become a better player. The win/loss patterns and streaks are fully consistent (in the mathematical sense) with the system as Blizzard describes it, and are not consistent with a system in which Blizzard forces wins and losses (34).

Matchmaking takes into account win percentage

It explicitly does not. “At no point in MMR calculations do we look at your win/loss ratio and win/loss ratio is never used to determine who to match you with or against. We are not trying to drive your win/loss percentage toward a certain number” – Jeff Kaplan (32). However, probability of winning depends the difference between MMR and a player’s skill level, and MMR does depend on how much a player has won or loss lately, so in this way there is an indirect dependence of win probability on win/loss history. This leads to (correct) statements that “Whenever I reach, or am near, my career high, I start losing and fall back down”. This corresponds to a player reaching his skill cap. The only way to break out of an MMR/SR range is to improve as a player and play a sufficient number of games.

Matchmaking takes people at a given SR, and then matches high skill players with low skill players to make a balanced match. Sometimes this is called handicapping, similar to amateur bowling or golf. This is done to achieve a 50% win percentage

This is not compatible with Blizzard’s statements: “All the system does when it comes to matching on skill is attempt to match you with people of a similar number” (32), and “We use MMR for matchmaking, not SR” (25) and “SR closely chases your MMR up and down and is a more “digestible” number. With the exception of top players who have decayed, MMR and SR are closely linked” (22). It is also contradicted by people’s ability to climb (13).

MMR is determined by statistical performance

The idea here is that a player’s MMR is really a summary of their statistical performance, and that because SR chases MMR (14), a player’s SR is basically determined by their statistical performance. If this were true, statistical performance would be, by far, the most important contribution to SR. This is contradicted by Blizzard (2) and by most players having a win percentage of about 50% (if statistical performance was weighted very heavily, stat-chasers would have much lower win percentage at a given SR than team-players, for example).

Matchmaking pushes a 50% win percentage using other broken criteria

It varies what this broken criteria is. The theories typically have a few things in common:

  1. Blizzard has never confirmed (and sometimes has denied) them.
  2. They would lead to obviously broken matchmaking.
  3. Their proponents never have solid data backing them up.
  4. They usually are not compatible with Blizzard statements, “All the system does when it comes to matching on skill is attempt to match you with people of a similar number” (32), and “We use MMR for matchmaking, not SR” (25).

The supposed support for these theories are that Blizzard has indicated that they desire and are happy with a 50% win percentage (32). However, there are many ways of accomplishing a 50% win percentage, and much better ways than the theories these forum writers ascribe to. Specifically, a 50% win percentage can be accomplished using a procedure similar to that which Blizzard describes (7): As a player wins matches, he is placed with and against stronger players. As he loses matches, he is placed with and against weaker players. With time, his win rate will converge to 50%, with some random oscillation around 50%. If he gets better (compared to the rest of the community), his win percentage will go up a bit until he finds his new level.

Blizzard is a company, and companies are inherently deceptive. See cigarette companies’ studies that indicate that cigarettes are good for you. Blue posts are not a reliable indicator of how the system works. My experience is proof that the system is malicious.

Yeah, well, you know, that’s just, like, your opinion, man.

More seriously, though, I take it as given that Blizzard employees don’t lie or intentionally mislead their customers. If you don’t agree, we don’t have much to discuss here. I can prove some things with data, but the much of the system will always be opaque if we disregard all the blue posts. Even if Blizzard open sourced their matchmaking and ranking code, people could claim that the available code is not actually implemented in the game.

Win Streak Bonus / Loss Streak Penalty

Prior to season 5 (June 1st, 2017), there was a substantial bonus to SR for winning many games in a row (about 4 or more), scaling all the way up to 150 SR for one win. To keep things balanced, penalties existed if a player lost many games in a row. This was removed because it lead to people who got lucky/unlucky being thrown far from their true rank (9, 10).

Leaver Penalty

Each time a player leaves competitive matches any time before the Victory/Defeat screen, he will receive a 50 SR penalty. It is not known if leaving penalizes players’ MMR. In addition, a leaver will receive increasing automatic bans, with each leave (19):

10 minutes
30 minutes
2 hours
8 hours
24 hours
Season Ban (with a season ban, no rewards are received)

The season ban cannot be reversed. The reason or method of leaving is irrelevant (43). If a player plays many games without leaving, the leaving penalty resets downward. The rule of thumb is that if the bans are getting into 8 or 24 hours, a season ban is imminent. If a player receives three season bans, a permanent ban is likely (30). The season bans do not need to be consecutive to count toward a permanent ban.

If the player leaves before the game is 30 seconds old, the match is cancelled and no one except the leaver is penalized/rewarded. If a player leaves after the game is 30 seconds old, Players on the leaver’s team get no consideration due to the leaver. That is, they (and the other team) gain and lose SR/MMR as normal. This is to prevent situations where it is the team’s interest for one person to leave and save everyone else from losing SR/MMR (and the winners from gaining SR/MMR) (41, 42).

If a player leaves and rejoins the match (after rebooting / internet comes back, etc.), he will often be able to save himself from getting the penalty, but it is not a sure thing. He needs to rejoin quickly, and not disconnect and reconnect several times (43).

Leaving during or after the Victory/Defeat screen is safe, but it does not save time before joining the next match. The matchmaker waits for the previous match to be complete before attempting to place players in a new match (44).


Because of the complexity of the system, subtle bugs with skill-rating and match-making can be difficult to spot and reproduce by the players. And many player reports are not particularly trustworthy for various reasons. However, there are some outstanding issues which are well-known and verified.

There are a number of reports of a bug that will cause people to have very small gains / large losses in the match after the match with a leaver (26), assuming the bugged player left after the game said it was safe to do so, but before the end of the match. To avoid this, never leave a match, even after the game says it is safe to do so. There are also a number of people who a have reported small gains or large losses without any leavers in the vicinity, so we do not entirely understand what is going on. However, Blizzard has said that there is a fix in the works (33) (or already done?) so we shall see.

There is a rare and serious bug in which players can get incorrectly season banned and lose huge and undeserved amounts of SR. It appears that what happens is a competitive game gets put in a “Waiting for Players” state. And each time the game restarts with new players, everyone loses 50 SR and gets an increasing ban, up to hundreds of SR and a season ban. Blizzard has acknowledged the problem, is working on it, and has promised restoration to affected players (31). However, restoration can be slow and painful. If you ever see “Waiting for Players” during a competitive match, you should exit by any means necessary to stop the bleeding.

Using statistical measures to rate players is particularly prone to subtle bugs (11), which Blizzard and players have been discovering and Blizzard has been (slowly) acknowledging, fixing, and re-implementing since launch.


(1) Welcome to Season 9 of Competitive Play - News - Overwatch
(2) Overwatch Forums The statement, “You go on a large win or loss streak, it gets less certain” is no longer valid, as win streak bonuses (and loss streak penalties) have been removed from the game.
(3) Overwatch Forums
(4) Overwatch Forums “In Overwatch, whether your MMR goes up or down is contingent on winning or losing. But there are a number of factors that determine how much that rating goes up or down.”
(5) Overwatch Forums
(6) Competitive Mode Tier Distribution
(7) Overwatch Forums
(8) Overwatch Forums
(9) Overwatch Forums
(10) Stevo, a twitch streamer and Symmetra main did a bronze to gm series on twitch after these changes went into effect, and there was no detectable SR bonus, even though he won 51 matches in a row. Analysis at Overwatch Forums.
(11) Overwatch Forums
Mercy Season 7 Analyzed - Google Sheets
(12) Full Overwatch Dev Talk w/ Scott Mercer - YouTube
(13) Overwatch Forums
(14) Overwatch Forums “When you do come back and actively play matches, you’ll also typically gain more SR from a win until your displayed skill rating and internal matchmaking have again reached ‘equilibrium’ “.
(15) Developer Update | Upcoming Season 6 Changes | Overwatch - YouTube
(16) Overwatch Forums
(17) Overwatch Forums
(18) Welcome to Season 4 of Competitive Play - News - Overwatch
(19) Overwatch Forums
(20) Overwatch Forums
(21) Overwatch Forums
(22) Overwatch Forums
(23) Overwatch Forums
(24) Season Placement Data - Google Sheets
(25) Note however, that the second sentence, “Also players’ displayed icon …” is no longer valid. Players’ icons now change as a player loses SR.
(26) Overwatch Forums
(27) Overwatch Forums
(28) Overwatch Forums
(29) Overwatch Forums
(30) Overwatch Forums
(31) Overwatch Forums
(32) Overwatch Forums
(33) Overwatch Forums
(34) Overwatch Forums
(35) Overwatch Forums
(36) Overwatch Forums
(37) Overwatch Forums
(38) Initial Competitive Skill Rating, Decrypted
(39) Season 9 Placements Analysis, High Variance Explained
(41) Overwatch Forums
(42) Overwatch Forums
(43) Overwatch Forums
(44) Leaving game when seeing defeat or victory - #8 by JeffreyKaplan
(45) Welcome to Season 2 of Competitive Play - News - Overwatch The 50 games restriction is currently in place. Decay has changed since this post. See the section on Rank Decay, above.
(46) Forced lose streak - #7 by Squirrel-12239
(47) Twitch

Last edited on 4/16/2018


Wow, just wow, great post, good job!


good post mate…


You seem to know a lot about these hidden things, so i will ask.

One friend S7 3300 end, 3400 carrier high, S8 placements - 1-9, he said he had awful games, overbuff shows awful stats for his main heroes during placements, however he still got 3700SR.

On the other hand other friend, S7 4000 end, carrier high 4300, S8 placemengs, 7-3, good stats during placements from overbuff, got 3700.

How is that possible please? I was examining it a lot but never really found answer. Can QP MMR be hiddenly connected to comp somehow even if you played seasons before?

Blizzard is really screwing up. It feels like they are punishing certain players and doing a lot of highly questionable things. Btw this new forum layout is a cool idea but ultimately is confusing and unnecessary. Why is there a scroll bar, when there’s already a fcking scroll bar. It really makes NO sense.


Quick play MMR is not connected to competitive MMR. This has been confirmed by Jeff.

I give my guesses for what may be going in the “Season Transitions” section in the original post. A newish possibility that occurred to me is that it may be related to the record from the previous season, wins, losses, and especially number of games played. If you could post placement results for season 9 (and season 8 record and finish) in it will help me gather data to test this hypothesis.

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  1. You seem to be missing, that map is also taken into account.
    You fail to take the first point on a 2CP and you lose, even though the first point is considered easy, you will lose more points than you would, if you at least took that one and lost later on.
    It’s one of the reasons as to why you can’t ban maps.

  2. What does “your position on the ladder” has to do with all of the above?
    Link source, please.

Uhm… a lot of what you say makes sense, which is why this particular quote is like a surprise slap in my face.

SR is your current rating, basically where you’re at in the given time. MMR is your estimated potential, if you will…
Why would they remove your current rating?! It doesn’t make any sense in the slightest…

Here is my problem with the MMR value being invisible::

If it were visible, you would be able to spot irregularities… say on your team everyone’s MMR is the same or lower than the SR, while on the enemy team everyone’s MMR is higher than their SR. Basically what I’m saying is that many matches seem to feel rigged, as if you didn’t get a fair match and are instead used as a stepping stone.

And hile this is completely hypothetical scenario, such a thing would explain the tendency of many matches (more than 50% of them) to be one-sided… and it would be a much better explanation, that the other also completely hypothetical ones like the Scott Mercer’s cats jumping on keyboards.

Also, it would be extremely useful for one to be able to see, if his MMR is lower than his SR, because then he would have an indication, that he is doing something wrong. ATM, you can’t see something like that, you can’t adequately analyze whether you’re doing something wrong, and thus you don’t have a tool to improve.

Another tool you don’t have to improve are replays. Blizzard have said, that they have internal replays. They also mentioned many times, that they plan to add them in the game.
Wanna know why? Because then you would be able to look the match from someone else’s perspective and easily report cheaters, throwers and the likes…


I have an alt account that is unplaced and has very similar stats to this one and in offseason got matched with diamond and high plat players, what’s wrong is that on the account I’m posting on is in high silver. So what is even the point of SR if the level of skill being shown at 2900sr is indistinguishable from 1800sr?
(inb4 “It’s offseason: no one cares”)

Without details of your other account you could be making this up.

C0derwatch has your SR at 1896… so…

Yeah more info needed.

I might have some plays tv clip(s) was in-game on that account, but I’m thinking about doing placements for it tonight or tomorrow.
Account in question:

I think map is probably taken into account in the performance modifier. However, I don’t have a blue post confirming this. Do you have a blue post reference backing it up?

I don’t put sources in the TLDR, but I do later:

From the reference, Diamond+ does not have the performance modifier and when near 5000 there is a SR nerf.

This is just wrong. MMR is Blizzard’s best estimate of your current ability, not your potential ability. The dominant factor in how it changes is wins and losses, but statistical performance is a minor factor, below diamond. Normally, MMR gets pushed up a bit on a win, and down a bit on a loss. Basically, you can never have a person with silver SR and plat MMR. The only time SR and MMR diverge substantially is with decay.

Blizzard has said many times that matching is based on MMR and SR doesn’t factor into it. See references (3, 21, 25, 40) in the original post.

I really don’t know how you can believe this. Watch and listen to the frustration in Jeff’s voice. And the “If you are a bad person, doing bad things in Overwatch, we don’t want you in Overwatch.”

With respect to the replay feature, they indicated (sorry, don’t have a link) that it was patch dependent. That is, every replay would get broken and be unwatchable every time there is a new patch. That makes the feature kinda beta. I believe they want to (and will) fix this and release a user friendly replay feature. But the wheels on the Blizzard bus turn slowly.

Yeah, I don’t really care (or know much) about the off season, sorry. Note also that quick play MMR is separate from competitive.

However, when you place on the alt account, you may well place substantially higher than your main. I talk about this, and other similar issues, in the section “How Accurate is SR” in the original post.

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So basically “trust Blizzard with 50% winrates everywhere and not flawed or get out”. If players couldn’t prove the MM is wrong, then Bliz didn’t prove it was right either. So you are clearly biased.

At same SR, if you get higher MMR gains by wins you get paired with lesser MMR players in your team to compesate against another team. You will have to climb as the “carry” player (better than your teammates, in MMR criteria), which is stupid if you play a support class or a tank class as carrying is more difficult (relying on the team cohesion to shine…).

The 50% or so winrates everywhere among players is not a sign of something working well to my mind. It is proof the MM is aiming at that (and successfully forcing it) which is not what a competitive mode should be. For me, randomness would be more fair than encouraged 50% winrates, and so removing MMR completely like any real comptetitive sport does.

Matchmaking pushes a 50% win percentage using broken criteria

It varies what this broken criteria is. Recent win percentage is popular. For example, a 75% win percentage player would be matched with a 25% win percentage player (on the same team). Another popular one is that a high stats player would be matched with a low stats player. The theories typically have a few things in common:

Blizzard has never confirmed (and sometimes has denied) them.
They would lead to obviously broken matchmaking.
Their proponents never have solid data backing them up.
They usually are not compatible with Blizzard statements, “All the system does when it comes to matching on skill is attempt to match you with people of a similar number” (32), and “We use MMR for matchmaking, not SR” (25).
The supposed support for these theories are that Blizzard has indicated that they desire and are happy with a 50% win percentage (32). However, there are many ways of accomplishing a 50% win percentage, and much better ways than the theories these forum writers ascribe to. Specifically, a 50% win percentage can be accomplished using a procedure similar to that which Blizzard describes (7): As a player wins matches, he is placed with and against stronger players. As he loses matches, he is placed with and against weaker players. With time, his win rate will converge to 50%, with some random oscillation around 50%. If he gets better (compared to the rest of the community), his win percentage will go up a bit until he finds his new level.

At a basic level, I believe that Blizzard employees never intentionally lie or mislead. If you don’t agree, we don’t have much to discuss. However, note that many people (myself included) have maintained > 50% win rates for hundreds of games and climbed much SR.

SR is not used in matchmaking, at all. Matchmaking is done by MMR alone. See

On a ladder system, that would be disaster. Most games would be stomps and a waste of time. GMs matched against bronzes, etc.

However, it is true that ladders have serious flaws that call them into question as a means of ranking players. It is always possible to game things by choosing who to play with, when to play, and how much to play. The only true competition is team vs team, league or tournament play. The team must remain a cohesive unit for the duration. Blizzard has implemented this for open, contenders, and overwatch league. Hopefully they will implement this for the lower skill players (or allow some third party to implement) at some point.

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At a basic level, I believe that Blizzard employees never intentionally lie or mislead.

Naive. And PTR uses prove that it is wrong. Pro players already complained years ago now on how patches are delivered. With lies. Any big software company has bigger issues to deal with compared to “not lying” it means nothing in business terms. Welcome to reality.

SR is not used in matchmaking, at all. Matchmaking is done by MMR alone.

It doesn’t change the fact that the higher is your MMR at a fixed SR, the lesser are the MMR of your teammates. It is indeed additions. Because SR != MMR. They actually improved it by simply destroying streaks and making SR ~= MMR in a shorter time. So fixing it is actually suppressing it, letting SR leading the way alone.

Linking to many things without quoting relevant data is lazy, all links don’t talk about MM based on MMR only (SR is obviously part of the equation, then MMR is used to match your teammates / opponents to my mind). You are extrapolating data.

On a ladder system, that would be disaster. Most games would be stomps and a waste of time. GMs matched against bronzes, etc.

With SR based only, a bronze can’t compete with a GM, as he doesn’t have enough SR to be within range for the MM.

Well I haven’t seen people cite their sources in a forum post before lol

Nah, not a blue post. I saw it in a video from Stylosa and he did say, that he heard it from the devs themselves. I would have to watch too many of those videos to be able to give you an exact link, he makes waaaay too many of those :stuck_out_tongue:
However, given the nature of the maps, I have no reason to doubt this. It would explain bigger points exchanges, that occur when I’m closer to where I’m usually at.

NVM, I turned off my brain for this one. Instead of “your position on the ladder”, you could have said “no personal performance modifier for Diamond+”, because for a second there, I thought you’re talking about something else.

I called it “potential”, because I’ve seen cases in other games when my MMR has been like 200 points higher, and yet I never reached it for one reason or another, without it dropping, or not by a large margin. But yeah, your definition is definitely better.
However, you fail to concede, that your statement of “abolish SR” was kinda dumb.

I don’t think how Jeff describes it is necessarily how it works.
There are people, that play Competitive, but don’t do it in a serious manner. They can waste your time, even though they don’t grief you on purpose.
I wouldn’t necessarily call them “bad people”, but many of them do bad things in competitive to a certain degree.
Do I agree, that they need to be banned from the game entirely? No.
But should they be allowed to participate in competitive and waste people’s time, even though it’s not obvious, deliberate griefing? I would argue, that the answer is No. There are certainly people, that should be banned from Comp at least temporarily, for a season or two without them necessarily being banned from the game entirely

I believe this, because I receive disproportionately low amount of notifications for actions taken when compared to the reports I send. And I guess you can argue, that I’m false reporting, but if that were the case – I would have been banned.

If there were a Replay feature, Blizzard would receive even more reports, than they do as of now. I don’t think they wanna deal with that.

There are other reasons. I picked up another game called Paladins. The setting is similar. However, I noticed, that there the matchmaking is worse. There are cases, that I would top the damage as a healer, and I would also outheal 3 other healers combined. Some players are clearly underperforming. Some are probably bots.
I thought to myself “well, at least I have Overwatch where the discrepancies in performance are not as crazy”… but then again, I really don’t know if that’s the case, because there is no score board.

So I believe, that what the game needs right now are:

  1. Visible MMR
  2. Score Board
  3. Replay feature
  4. Avoid player feature (preventing players from being placed on your team, not in your match entirely in order to avoid abusing the feature, by blocking good players from being placed against you)

These would be great tools, that would allow players to improve themselves and be better players, but I believe Blizzard are reluctant to provide those. Specifically in the case of the Replay feature, I believe it’s because Blizzard don’t wanna have to handle all those reports. I hope I’m wrong, but the frustration in Jeff’s voice does not convince me.
The whole “replays get broken from patch to patch” is irrelevant, because you can make a video recording of the parts you need, and you can save it on an external hard drive, youtube or a cloud and it would be available, even if the replay itself get’s broken.
That’s no excuse as to why it’s been almost two years, and there are still no replays.
I wanna be able to analyze my mistakes, but I already have the tools to do so. I can record a video and see what I’m doing.
But on the other hand, I wanna be able to see from the perspective of my allies and see what they are doing. I wanna be able to look at the full picture, that’s all.

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MMR is translated into your SR, with the translation factoring in things such as SR decay for inactive players whose SR translated over 3000 or penalties for leaving a comp game in the middle. It is NOT some kind of value that differentiates players of the same SR (that is, it is NOT a value that shows one SR2500 player really being a 2800 and another SR2500 player really being a 2200 and thus they get put together in one team).

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Yeah, don’t worry about it. I tend to agree with Stylosa, but he blathers on and on, and I don’t consider him saying something to be proof of anything.

Other games as in “not Overwatch”? I’m not sure how that’s relevant.

Well, I don’t think it is dumb. However, we agree on the important thing, that competitive MMR should be visible.

I agree with 1, 3, and 4. I think 2 would increase toxicity, but I’m not excited enough about it either way to get in a debate. 1 is possible, but would require blizzard to do some “deep soul searching” once more. Blizzard has made no comment on 2. 3 I expect to get implemented … eventually. I would be surprised if 4 happens. I don’t think Blizzard trusts us with that kind of power.

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