How is DPR calculated?

DPR is your hit chance times average damage on a hit, plus extra damage from crits. A crit doubles the damage dice but not the flat modifier, so the tool computes (hit minus crit chance) times normal hit damage, plus crit chance times crit damage, then multiplies by your number of attacks.

Does it handle critical hits correctly?

Yes. On a critical hit you roll the damage dice twice but add the flat modifier only once. The calculator separates the crit portion of your hit chance and applies doubled dice to it, which is the official 5e rule and a common source of errors in hand math.

How does advantage affect DPR?

Advantage raises your hit chance and roughly doubles your natural-20 crit chance, both of which increase DPR. Select advantage or disadvantage and the tool recomputes the per-face probabilities exactly, so you can see the real damage swing from a feature like Faerie Fire.

Where do I put my Strength or Dexterity bonus?

Put ability and other flat bonuses in the flat damage modifier field, and keep only dice like 1d8 in the dice field. Flat bonuses are added once per hit and are not doubled on a crit, so separating them keeps the math correct.

Can I model an expanded crit range like a Champion Fighter?

Yes. Set the crit range to 19-20 or 18-20 to model a Champion Fighter's Improved Critical. A wider crit range increases the share of hits that deal doubled dice, raising DPR, especially for builds with large dice or extra crit dice.

D&D Damage Per Round (DPR) Calculator

Compare D&D 5e builds with real numbers instead of vibes. Enter your attack bonus, the target’s AC, your damage dice, and crit range, and this calculator returns your hit chance and average damage per round with correct critical-hit math and full advantage support.

How it works

Your hit chance is the probability that d20 + attack bonus ≥ AC, with a natural 20 always hitting and a natural 1 always missing. A critical hit occurs on a natural roll in your crit range (20, or 19-20, or 18-20), and crits are a subset of your hits.

A crit doubles the damage dice but not the flat modifier, so:

DPR (one attack) =
    (hitChance − critChance) × (avgDice + flatMod)
  +  critChance × (2 × avgDice + flatMod)

The tool averages your dice expression (each NdF averages N × (F+1)/2), applies advantage or disadvantage by recomputing per-face probabilities exactly, and multiplies by your number of attacks for total DPR.

Tips and example

A +7 attack against AC 15 hitting with a 1d8+4 longsword (one attack) lands around 8-9 DPR; add Extra Attack by setting attacks to 2 to roughly double it.
Toggle advantage to see why granting yourself advantage is often worth more than a small static bonus, especially with extra crit dice like a Paladin’s smite.
Keep flat bonuses in the flat field so they are correctly added once per hit and never doubled on a crit.