How exactly do item levels and character levels compare?

I was doing some legacy raids today and realised I have absolutely no idea what the difference is between character level, and ‘equivalent’ character levels granted by item level, which is meant to be around 15 item levels = 1 character level. Or thereabouts.

Let’s say I am doing Mythic Shadowlands Sanctum of Domination. The gear drops there are around 250. So let’s say, for example, that those level 62 bosses have the equivalent of item level 250. So far so good. If you are level 62 with item level 250 gear, you should be at the same ‘level’ as the boss, right?

Now. You level to 70, and you increase your gear to item level 400. So now your character level is 8 levels higher than those level 62 bosses, and in item levels you have gained 10 ‘equivalent’ character levels, e.g. 250 to 400 is 150 item levels, which is meant to be 10 character levels.

Is this correct? Are you now the equivalent of 18 character levels above those bosses?

What about Raid Finder bosses which are also at level 62? Normal? Heroic?

What about Battle for Azeroth raids? Let’s say one of those bosses is at the equivalent of item level 140. The difference there is now 90 item levels away from our level 62 Shadowlands bosses, and 10 character levels. Is the number of equivalent character levels for our level 70 item level 400 guy now: level 52 vs level 70 = 18 levels, and 140 to 400 = 16 character levels, for a total difference of 18 + 16 = 34 character levels?

Is there an absolute quantifiable amount your power goes up ‘per level’ or is it ALWAYS DIFFERENT and there is no ACTUAL and definite difference between character levels and those granted by items?

Is the difference between item level 100 to 115 exactly the same as between item level 400 and 415?

Is the difference between character level 30 to 31, and 60 to 61, exactly the same?

Please help an old wolf to understand. Thank you.

Character level and gear ilvl has nothing in common. They’re two completely different things.

Character level is just an artificial path of progression that provides increasing character stats and new skills/talents.

Gear ilvl is dependant on the power blizzard gave the gear at the time it was implemented into the game.

I think you’re waaaaay overthinking this, tbh.

I’m curious why you want to know this, anyway. Are you just trying to figure out what you can solo? Or is it just something you want to know for the sake of knowing?

My little Vulpera brain went kablooey. Why? Just why? Go try and solo stuff and find out.

This isn’t really something worth worrying about.