Dice Average Calculator
Two six-sided dice (2d6) average 7 per roll, and 13d8 averages 58.5. This dice average calculator gives the expected value of any dice pool in standard NdS notation, plus a flat modifier if your game adds one. It also shows the minimum and maximum possible totals, the full range your rolls can land in.
Quick answer
A single die averages the midpoint of its faces: (sides + 1) / 2. A d6 averages 3.5.
Average roll (2d6)
7
Minimum
2
Maximum
12
What this tells you
- •A single die averages the midpoint of its faces: (sides + 1) / 2. A d6 averages 3.5.
- •Multiple dice just multiply that midpoint. 2d6 averages 2 x 3.5 = 7.
- •A flat modifier shifts the average directly. 2d6+3 averages 10.
- •More dice also means totals bunch around the average, single big dice stay wild.
How to Use
- 1Enter how many dice you roll.
- 2Enter the sides per die, like 6 for d6 or 20 for d20.
- 3Add any flat modifier, positive or negative.
- 4Read the average, minimum, and maximum for the pool.
How It Works
Formula
average = N x (S + 1) / 2 + modifierEach die's faces run 1 to S, and their average is the midpoint (S + 1) / 2. Averages add across dice, so N dice average N times the midpoint. For 13d8 that is 13 x 4.5 = 58.5. The minimum is all ones (N + modifier) and the maximum is all top faces (N x S + modifier).
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
Classic 2d6
Each d6 averages 3.5, and two of them average 7, the most common total in many board games.
13d8 damage pool
A d8 averages 4.5, times 13 dice gives 58.5.
Greatsword with a strength bonus (2d6+4)
The +4 shifts every outcome, including the 7 average, up by 4.
Average Roll per Die Type
Midpoint value of each common gaming die.
| Die | Average | 10 dice average |
|---|---|---|
| d4 | 2.5 | 25 |
| d6 | 3.5 | 35 |
| d8 | 4.5 | 45 |
| d10 | 5.5 | 55 |
| d12 | 6.5 | 65 |
| d20 | 10.5 | 105 |
| d100 | 50.5 | 505 |
Common mistakes
- Averaging a die as S / 2 instead of (S + 1) / 2. A d6 averages 3.5, not 3, because the faces start at 1 rather than 0.
- Multiplying the modifier by the dice count. 2d6+3 adds 3 once, not per die.
- Expecting the average on every roll. Half your rolls land below it, and single-die rolls spread evenly across the whole range.