Compare2d6+5 @ AC15 +9 vs 2d6r1+5 @ AC15 +9

2d6+5 @ AC15 +9 vs 2d6r1+5 @ AC15 +9

Side-by-side distributions with exact probabilities. Edit either expression or drag the HP slider — the URL updates as you go, so the page stays shareable. expression syntax →

Strike A

Roll 1 twenty-sided die. Add +9. Compared against AC 15: you hit if the kept d20 face plus the bonus totals 15 or more (so the d20 needs to land on at least 6). A natural 20 always crits, regardless of AC. On a hit, deal 2 6-sided dice, plus 5. On a crit, double the damage dice (the 2d6+5 becomes 4d6+5); flat modifiers stay the same.

min 0 max 29 mean 9.35 187/20 ±6.01
P(finish at 10 HP) = 63.33% (3283/5184)
  • 0 25.00%
  • 1 0.00%
  • 2 0.00%
  • 3 0.00%
  • 4 0.00%
  • 5 0.00%
  • 6 0.00%
  • 7 1.94%
  • 8 3.89%
  • 9 5.84%
  • 10 7.79%
  • 11 9.76%
  • 12 11.74%
  • 13 9.86%
  • 14 7.99%
  • 15 6.14%
  • 16 4.29%
  • 17 2.43%
  • 18 0.54%
  • 19 0.56%
  • 20 0.54%
  • 21 0.48%
  • 22 0.40%
  • 23 0.31%
  • 24 0.22%
  • 25 0.14%
  • 26 0.08%
  • 27 0.04%
  • 28 0.02%
  • 29 0.00%
Strike B

Roll 1 twenty-sided die. Add +9. Compared against AC 15: you hit if the kept d20 face plus the bonus totals 15 or more (so the d20 needs to land on at least 6). A natural 20 always crits, regardless of AC. On a hit, deal 2 6-sided dice (reroll any 1 once), plus 5. On a crit, double the damage dice (the 2d6r1+5 becomes 4d6r1+5); flat modifiers stay the same.

min 0 max 29 mean 10.02 601/60 ±6.31
P(finish at 10 HP) = 70.79%
  • 0 25.00%
  • 1 0.00%
  • 2 0.00%
  • 3 0.00%
  • 4 0.00%
  • 5 0.00%
  • 6 0.00%
  • 7 0.05%
  • 8 0.76%
  • 9 3.40%
  • 10 6.05%
  • 11 8.70%
  • 12 11.35%
  • 13 13.26%
  • 14 10.64%
  • 15 8.06%
  • 16 5.50%
  • 17 2.97%
  • 18 0.45%
  • 19 0.56%
  • 20 0.63%
  • 21 0.65%
  • 22 0.60%
  • 23 0.50%
  • 24 0.38%
  • 25 0.25%
  • 26 0.14%
  • 27 0.07%
  • 28 0.03%
  • 29 0.01%

B finishes in 1.41 strikes vs A's 1.54 — B wins by 0.13 strikes.

Strikes to kill 10 HP expected: 1.54
  • ≤ 1 63.33%
  • ≤ 2 87.91%
  • ≤ 3 96.25%
  • ≤ 4 98.88%
  • ≤ 5 99.67%
Strikes to kill 10 HP expected: 1.41
  • ≤ 1 70.79%
  • ≤ 2 91.64%
  • ≤ 3 97.65%
  • ≤ 4 99.35%
  • ≤ 5 99.82%