Odds of rolling 18 on 3d6
Three sixes, and the hardest roll in the set.
Chance per roll
0.46%
1 of the 216 ways 3 6-sided dice land add up to 18 — about one roll in 216.0. Among the 16 totals 3d6 can make, that is the 2nd least likely of 16 — tied with 1 other, since the distribution is symmetric.
Every total 3d6 can roll, with 18 picked out. The peak is 10 at 12.50%.
The 1 way to make it
Every one of them, which is the whole proof of the figure above — count the rows, divide by 216.
Other rolls worth knowing
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