Damage Per Round Calculator
Estimate average damage per round from your attack’s damage dice, attack bonus, target AC and number of attacks, including critical hits. Calculates in your browser.
Damage per round
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Show the math
Each attack's expected damage weights a normal hit and a critical hit by their chances on a d20 (a natural 20 always crits, a natural 1 always misses):
per attack = P(hit)·(dice+bonus) + P(crit)·dice
A planning estimate, it ignores resistances, save effects and conditions. All math runs locally in your browser.
What this does
A damage per round calculator estimates average damage per round from your attack’s damage dice, attack bonus, target AC, and number of attacks, including critical hits.
How to use it
- Enter the damage dice and bonus.
- Enter your attack bonus.
- Enter the target AC.
- Set the number of attacks.
How it works
A natural 20 always hits and doubles the damage dice; a natural 1 always misses. A hit never deals less than 0, so a big penalty can’t turn into negative damage. It ignores resistances and conditions.
DPR = hit chance × damage × attacks (+ crit)
Understanding your result
This averages damage across hits, misses, and crits, so it is a theoretical baseline for comparing builds, not what any single round will deal. It ignores resistances, conditions, and limited resources, so real damage is often lower. The figure rewards accuracy as much as raw dice: more attacks that reliably hit usually beats one big swing that often misses.
Example
Three accurate attacks of 1d8+3 can average over 20 damage a round.
Last updated .
Frequently asked questions
How are critical hits handled?
A natural 20 always hits and doubles the damage dice (but not the flat bonus); a natural 1 always misses.
Does this account for everything?
It is a planning estimate, it ignores resistances, saving-throw effects and conditions.
Is my data kept?
No. Everything is computed locally in your browser.
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