Work out the odds of a dice roll

Does the party hit on 4d6 ≥ 14? Exact probabilities for any NdS roll — no simulation noise, no mental arithmetic.

Tools used in this guide

The job

Tabletop games run on dice sums — ability checks, damage rolls, success thresholds. Knowing that 4d6 ≥ 14 is about 62 % changes the plan more than hoping does.

Set up the roll

Enter dice count and sides — 4d6, 2d20, 8d10 — pick the condition (at least, at most, exactly, between), and read the probability as a fraction, a decimal, and a percentage.

The distribution table shows every total's exact share — useful for picking a fair threshold.
"Between" covers ranges like 10–14 inclusive.

Worked example

3d6 ≥ 10: 162 of 216 outcomes — exactly 75 %. The peak of the distribution sits at 10–11, which is why "roll under 10" and "roll 10 or more" feel like coin flips.

What it assumes

Fair, independent dice. Advantage/disadvantage mechanics, dice pools that explode, and loaded dice aren't modelled — the math is exact sums of uniform dice only.

Limits: 50 dice, 1,000 sides, and count × sides ≤ 20,000.
For actually rolling the dice rather than computing odds, use the dice roller.