Can someone explain how CD reduction is calculated?
I have the following CD reduction:
- 10.2 from helm
- 7.2 from amulet
- 16.1 from ring
- 26.6 from focus
This should add up to 60.1 percent cooldown reduction. However, my stats are reading 47.7.
Cooldown Reduction is multiplicative. For example
Your skill has a 30 second cooldown. You are wearing:
- Helm: 6% cooldown reduction
- Amulet: 4% cooldown reduction
- Offhand: 7% cooldown reduction
You don’t just add these percentages together.
Subtract each reduction percentage from 100% (because you want to know how much is left after the reduction):
- Helm: 100% - 6% = 94%
- Amulet: 100% - 4% = 96%
- Offhand: 100% - 7% = 93%
Multiply these percentages together:
- 0.94 × 0.96 × 0.93 = 0.839904
Subtract that result from 1 to find the total reduction:
- 1 - 0.839904 = 0.160768 x 100 = 16%
So 16% of 30 is 4.8 meaning your skill has a new cooldown of 25.2 seconds.
How is the figure in the stats and materials (under utility) calculated?