How the 40k damage calculator works

Pick an attacker and a target, and the calculator plays out the attack sequence of Warhammer 40,000's 11th edition: hit rolls, wound rolls, saving throws, then damage, with re-rolls, modifiers, leaders and detachment rules where they apply. That is mathhammer: the average the dice give, and the odds of every other outcome, so you know what a unit really does before you build a list or commit to a play.

A worked example, the matchup the calculator opens on. 5 Intercessors fire 10 bolt rifle shots at 10 Termagants. Hitting on 3+ gives 6.67 hits on average. Strength 4 against Toughness 3 wounds on 3+: 4.44 wounds. The Termagants' 5+ save becomes 6+ against AP −1, so 3.70 wounds get through, and at 1 damage each that is about 3.7 Termagants slain. Standing still first (the bolt rifle is Heavy: +1 to hit) makes it 4.6. The calculator goes on to add the rest of the squad's wargear and its fight, so its total is higher.

More in the mathhammer guide, how we score units and every army's tier list.