Mathhammer guide · Warhammer 40K 11th Edition · verify current profiles and rules

How do you use 40K damage probability to make better trades?

Start with what the play must accomplish, then enter the real attacker, defender, weapons, and supported modifiers. Read average damage, models destroyed, wipe probability, and the kill distribution as a range rather than a promise. Compare that range with the mission need, the cost of failure, and the opponent’s likely return trade.

What is the difference between a result and a decision?

A damage roll tells you what happened once. Probability helps you judge whether taking that line was reasonable before the dice. A sound attack can roll low, and a poor attack can spike. Review the range you accepted, the mission value you expected, and what the failed attack would expose.

How do you define success before calculating?

Write the requirement in game terms. Do you need to remove one model to reduce Objective Control, clear the whole unit to open a charge lane, bracket a vehicle, or merely force a defensive resource? The calculator does not own a custom success-threshold control, so compare its average, wipe chance, and kill distribution with the requirement you wrote.

How should you set up the attacker and defender?

The free Damage Calculator works without an account. Enter the profiles directly, use a saved calculator loadout, choose a recent unit name as a shortcut, or send selected models from the tabletop. Board-selected attackers use their live weapon data. Selected defenders must share one defensive profile. Always verify model count, stats, weapons, and modifiers before calculating.

The searchable name picker does not supply official weapon or stat profiles. The built-in unit lookup elsewhere in 40 Carrot provides names, base sizes, and current official points, not complete datasheets.

How do you read the output without treating it as a promise?

• Average damage is the long-run center, not the most important outcome in every position.
• Average models destroyed translates damage into the defender’s wound and model profile.
• Wipe probability shows how often the attack clears the full defender under the entered assumptions.
• Kill distribution shows how often each model-loss result occurs and exposes a wide or narrow range.

How do you price the whole trade?

Add the movement and scoring consequences around the attack. Which unit must leave cover? What objective changes hands? Does a second activation become available if the first falls short? Which enemy unit can answer? A better damage number can still be a worse trade if the attacker gives up more score or material.

How do you compare two attack plans?

Keep the defender and mission requirement fixed. Change one choice at a time: target, weapon split, supported modifier, or participating unit. Compare the distribution and wipe chance, then compare the positions each plan creates. Do not change both the math and the opponent’s response in the same first pass.

What should you review after the dice are rolled?

Ask whether the actual result sat inside the plausible range and whether your decision accounted for the lower end. If the play needed a wipe but the wipe probability was too low for the cost, the lesson is about risk. If the chance was acceptable and you rolled low, the lesson may be to keep the same decision.

Use the game review method to rebuild the position and test the alternative without changing everything else.

How can you build a small matchup library?

Save named calculator loadouts for the attacks and defensive profiles you face often. Label the real condition, such as “basic shooting, no external buffs” or “melee with supported hit modifier.” Recheck every profile after a rules or datasheet update. The saved loadout is your entered reference, not an official rules source.

What does this look like in an objective trade?

An enemy unit holds a neutral objective. Your first option sends one valuable unit to shoot and charge; your second uses two cheaper activations while keeping the valuable unit staged. Calculate each attack with the same defender. Then compare how often each clears enough models, which units become exposed, and which plan leaves a useful follow-up if the first activation falls short.

Frequently asked questions

What does 40K damage probability tell me?

With the profiles and supported modifiers you enter, 40 Carrot calculates average damage, average models destroyed, wipe probability, and the kill distribution. Those outputs describe a range of possible results. They do not choose the target, price the return trade, or guarantee an outcome.

Is the 40 Carrot Damage Calculator free?

Yes. The Damage Calculator is free and works without an account. You can enter profiles directly on its public page. Inside the tabletop, you can also send selected board models to the calculator and use live attacker weapon data.

Why is average damage not enough?

An average hides how often low and high results occur. Read the kill distribution and wipe probability beside the average, then compare them with what the play needs to accomplish. A line can have a strong average and still fail too often for the mission situation.

Does the calculator include every 40K rule and modifier?

No. It supports the modifiers listed in the calculator, but it does not know every rule interaction. Enter the current profiles and applicable effects, check the displayed hit, wound, and save assumptions, and use current official rules to resolve anything the calculator does not model.

Does the unit picker supply official weapon and stat profiles?

No. The searchable picker is a name and model-count shortcut, not a source of official profiles. Use a saved calculator loadout, a recent unit-name choice, or selected board models, then verify or enter the real stats, weapons, and supported modifiers yourself.