Attack speed is a game term used to describe the delay between attacks, measured in seconds; the reciprocal of the actual rate of attacks. Essentially, it can be considered the "cooldown" between attacks by the given weapon. It is determined by the weapon you wield and (if applicable) enchantments on said weapon.
Attack speed calculation
- Attack_speed = "current attack speed" / (("Percent increase or decrease" / 100) + 1 )
You must apply this formula for each speed buff you apply.
Basically all of the calculations are reciprocal operations and are inverted from how you would expect to see them.
- Weapon speed = 1.8
- Slice and Dice = 40%
- Blade Flurry = 20%
- JuJu Flurry = 3%
- Attack_speed = 1.8 / ( (40 / 100) + 1 ) = 1.2857
- Attack_speed = 1.2857 / ( (20 / 100) + 1 ) = 1.0714
- Attack_speed = 1.0714 / ( (3 / 100) + 1 ) = 1.0402
So with all 3 speed buffs going the attack speed is now 1.0402
- 1.8 / 1.0402 = 1.73 = 73% increased attack speed
Or, in attacks per minute:
- 57.6812 / 33.3417 = 1.73 = 73% more attacks per minute
Note: Blizzard rounds to 4 significant digits.
Blizzard applies attack speed buffs multiplicatively; in this example the buffs provide 73% increase, because 40% increase times 20% increase times 3% increase is 1.4 * 1.2 * 1.03 = 1.7304.
If you flip the numerator and denominator, you get your number of attacks per second, meaning that a percentage increase in attack speed has the final result of increasing your damage per second by the same percentage, along with an added bonus of increasing the number of ability procs (from weapons or skills and talents like Improved Aspect of the Hawk).
A quick way to determine resultant attack speed, without applying the formula for each increase, is the following:
[current attack speed] / (increase1 * increase2 * increase3...etc)
1.8 / (1.40 * 1.20 * 1.03) = 1.0402
Improving attack speed
Various sources that improve attack speed are listed on the attack speed improvement page.
- Patch 1.7.0 (patch date:2005-09-22): Spells and effects that reduce attack speed will no longer stack with each other.