Compare1d8+5 @ AC15 +9 vs 1d8+15 @ AC15 +4

1d8+5 @ AC15 +9 vs 1d8+15 @ AC15 +4

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 1 8-sided die, plus 5. On a crit, double the damage dice (the 1d8+5 becomes 2d8+5); flat modifiers stay the same.

min 0 max 21 mean 7.35 147/20 ±4.81
P(finish at 9 HP) = 48.52% (621/1280)
  • 0 25.00%
  • 1 0.00%
  • 2 0.00%
  • 3 0.00%
  • 4 0.00%
  • 5 0.00%
  • 6 8.75%
  • 7 8.83%
  • 8 8.91%
  • 9 8.98%
  • 10 9.06%
  • 11 9.14%
  • 12 9.22%
  • 13 9.30%
  • 14 0.63%
  • 15 0.55%
  • 16 0.47%
  • 17 0.39%
  • 18 0.31%
  • 19 0.23%
  • 20 0.16%
  • 21 0.08%
  • 22 0.00%
  • 23 0.00%
  • 24 0.00%
  • 25 0.00%
  • 26 0.00%
  • 27 0.00%
  • 28 0.00%
  • 29 0.00%
  • 30 0.00%
  • 31 0.00%
Strike B

Roll 1 twenty-sided die. Add +4. 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 11). A natural 20 always crits, regardless of AC. On a hit, deal 1 8-sided die, plus 15. On a crit, double the damage dice (the 1d8+15 becomes 2d8+15); flat modifiers stay the same.

min 0 max 31 mean 9.97 399/40 ±10.16
P(finish at 9 HP) = 50.00% (1/2)
  • 0 50.00%
  • 1 0.00%
  • 2 0.00%
  • 3 0.00%
  • 4 0.00%
  • 5 0.00%
  • 6 0.00%
  • 7 0.00%
  • 8 0.00%
  • 9 0.00%
  • 10 0.00%
  • 11 0.00%
  • 12 0.00%
  • 13 0.00%
  • 14 0.00%
  • 15 0.00%
  • 16 5.63%
  • 17 5.70%
  • 18 5.78%
  • 19 5.86%
  • 20 5.94%
  • 21 6.02%
  • 22 6.09%
  • 23 6.17%
  • 24 0.63%
  • 25 0.55%
  • 26 0.47%
  • 27 0.39%
  • 28 0.31%
  • 29 0.23%
  • 30 0.16%
  • 31 0.08%

A finishes in 1.80 strikes vs B's 2.00 — A wins by 0.20 strikes.

Strikes to kill 9 HP expected: 1.80
  • ≤ 1 48.52%
  • ≤ 2 80.51%
  • ≤ 3 93.47%
  • ≤ 4 97.95%
  • ≤ 5 99.39%
  • ≤ 6 99.82%
Strikes to kill 9 HP expected: 2.000
  • ≤ 1 50.00%
  • ≤ 2 75.00%
  • ≤ 3 87.50%
  • ≤ 4 93.75%
  • ≤ 5 96.88%
  • ≤ 6 98.44%
  • ≤ 7 99.22%
  • ≤ 8 99.61%