Minecraft wiki entry for Damage, associated text: The attackSpeed attribute controls the length of the cooldown time, with the time taken being T = 20 / attackSpeed ticks. The damage multiplier is then 0.2 + ((t + 0.5) / T) ^ 2 * 0.8, restricted to the range 0.2 – 1, where t is the number of ticks since the last attack or item switch.