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6d6 Dice Probability — Full Distribution and Odds

Six dice is the largest pool most people can add in their head, and the curve already looks like a bell. The sum runs from 6 to 36, the average is 21, and the most likely total is 21. Below is every sum with its exact number of ways, its probability, the cumulative odds and the "at least" thresholds worth memorising.

Range6 – 3646,656 outcomes
Average21σ = 4.18
Most likely219.28%

Every possible sum

SumWaysExactlyAt mostAt leastOdds of exactly
610.002%0.002%100.0%1 in 46656
760.013%0.015%100.0%1 in 7776
8210.045%0.060%100.0%1 in 2222
9560.120%0.180%99.9%1 in 833
101260.270%0.450%99.8%1 in 370
112520.540%0.990%99.5%1 in 185
124560.977%1.97%99.0%1 in 102
137561.62%3.59%98.0%1 in 61.7
141,1612.49%6.08%96.4%1 in 40.2
151,6663.57%9.65%93.9%1 in 28
162,2474.82%14.5%90.4%1 in 20.8
172,8566.12%20.6%85.5%1 in 16.3
183,4317.35%27.9%79.4%1 in 13.6
193,9068.37%36.3%72.1%1 in 11.9
204,2219.05%45.4%63.7%1 in 11.1
214,3329.28%54.6%54.6%1 in 10.8
224,2219.05%63.7%45.4%1 in 11.1
233,9068.37%72.1%36.3%1 in 11.9
243,4317.35%79.4%27.9%1 in 13.6
252,8566.12%85.5%20.6%1 in 16.3
262,2474.82%90.4%14.5%1 in 20.8
271,6663.57%93.9%9.65%1 in 28
281,1612.49%96.4%6.08%1 in 40.2
297561.62%98.0%3.59%1 in 61.7
304560.977%99.0%1.97%1 in 102
312520.540%99.5%0.990%1 in 185
321260.270%99.8%0.450%1 in 370
33560.120%99.9%0.180%1 in 833
34210.045%100.0%0.060%1 in 2222
3560.013%100.0%0.015%1 in 7776
3610.002%100.0%0.002%1 in 46656

Rolling a target or higher

This is the form most checks actually use — "did I beat 12?" rather than "did I roll exactly 12".

TargetChance of meeting itOdds
≥ 1785.5%1 in 1.17
≥ 1972.1%1 in 1.39
≥ 2245.4%1 in 2.2
≥ 2520.6%1 in 4.86
≥ 279.65%1 in 10.4

Reading the shape

Each die is uniform, but the sum is not. 6d6 has 46,656 ordered outcomes spread over 31 totals, and the counts rise toward the middle because a middle total can be assembled from more orderings. The curve is symmetric around 21 — for every way to roll 20 there is a mirrored way to roll 22 — which is why the standard deviation of 4.18 describes the spread on both sides equally.

Compare that with a single die: 1d6 is a flat line at 16.7% per face. Adding dice does not widen the range proportionally — it makes extreme results rarer. That is the whole reason systems that want predictable outcomes roll pools, and systems that want drama roll one big die.

Frequently asked

What is the average roll of 6d6?
21. The formula is dice × (faces + 1) / 2 — 6 × (6 + 1) / 2 — which works for any fair die. The standard deviation is 4.18, so most rolls land between 16 and 26.

What is the most likely total on 6d6?
Exactly 21, at 9.28% — 4,332 of the 46,656 equally likely outcomes. The extremes (6 and 36) take 1 way each, or 0.002%.

How many possible outcomes does 6d6 have?
46,656 ordered outcomes — 66 — collapsing into 31 possible sums from 6 to 36. The counts here are exact integers from a convolution, not a normal approximation, so the tails are right: a normal curve would misstate the odds of the extreme rolls.

Why is the middle so much more likely than the ends?
Because sums have more ways to happen than faces do. There is exactly one way to roll all ones, but a middle total can be assembled from many orderings, and each ordering is a distinct outcome. That is why 6d6 has a single peak at 21 and why adding dice makes the distribution tighter rather than wider.

Nearby pools

5d6