4d6 = 21
Rolling 4 dice, 20 of the 1,296 outcomes add up to 21 — a 1.54% chance.
Probability
1.54%
Ways for each sum
- Ways to roll it
- 20 / 1,296
- Probability
- 1.54%
- One roll in
- 64.8
- This or higher
- 2.7%
- This or lower
- 98.84%
- Average sum
- 14
Nearby sums
Rolls with similar odds
A different number of dice can land on much the same chance.
How to read this
- Two dice do not land evenly. There are six ways to make 7 and only one way to make 2.
- The more dice, the tighter the middle. With six dice almost everything lands near 21, while 6 or 36 turns up about once in 47,000 rolls.
- The average sum is 3.5 per die, because one die averages 3.5.
- Rare is not never — but nor is it due. Roll two dice thirty-six times and there is still roughly a 36% chance you never see a 2.
Frequently asked questions
Q. What are the odds of rolling 21 on 4 dice?
1.54% — 20 of 1,296 possible rolls, or roughly one roll in 64.8.
Q. How often do I roll 21 or more?
2.7% of the time. Rolling 21 or less happens 98.84% of the time.
Q. What is the most likely sum with this many dice?
Something near the average of 14. 13 sums come up more often than 21.
Q. Will it definitely turn up if I keep rolling?
No. Each roll is independent of the last. One in 64.8 is a long-run average, not a schedule.