Dice probability
Explore exact dice-sum outcome counts and chances of reaching a target. Drag the graph handles to change inputs and explore the result.
Your inputs
These editable values illustrate the calculation. Replace them with your own inputs. Results update as you edit.
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How it works
- 1 ≤ face ≤
- C₀(0) = 1; () = Σ ₋₁( − face); Probability = Favorable outcomes / Total equally likely outcomes × 100
- Worked example: 2 × d6; s = 7 ⇒ 6 / 36 = 16.66666667%; max(d6,d6) ≥ 5 ⇒ 1 − (4/6)² = 55.55555556%
Input and formula key
Your result
Complete the inputs to see your result.
Assumptions and limitations
Use 1–20 identical fair, independent dice with 2–100 sides numbered from 1. Higher/lower modes roll two independent complete pools and select the higher/lower sum. Counts use exact integers; percentages are decimal approximations. This generic rule is not a game-specific mechanic. Rerolls, exploding dice, modifiers and publisher-specific rules are excluded.
Sources
- OpenStax — fair dice probability Sources reviewed: 2026-10-08
