DicePlots

Diceplots computes exact probability distributions for dice expressions and answers the questions every TTRPG and ARPG player has at the table: - "Will my 2d6+5 actually drop a 14-HP target?" → 13/18, or 72.22%. - "Greataxe (1d12+5) or greatsword (2d6+5)? Same mean — different shape." See exactly where the curves cross. - "How much does advantage on a d20 actually help?" Closed-form skew, not vibes. - "How many strikes until I finish 80 HP?" Expected strikes plus the full per-strike kill curve. The engine convolves exact rationals — no Monte Carlo, no "I ran 100,000 simulations" approximations. Every number is computable on paper; we just do it in microseconds. EXPRESSION SYNTAX The full notation, at a glance: 2d6 roll two six-sided dice, sum the faces 2d6+5 add a constant 1d8 + 1d6 + 3 mix any number of terms 1d6! exploding dice — max face rolls again, sums in 2d6r1+5 reroll once on a 1 (Great Weapon Fighting) 2d20kh1 keep highest of 2d20 (advantage) 2d20kl1 keep lowest of 2d20 (disadvantage) WHAT YOU GET For every expression: - Exact rational mean, variance, and skewness — closed-form when available, hovered tooltips on every percentage. - Per-outcome bar chart with the exact rational on tap. - Kill probability vs any HP target. - Strikes-to-kill chain — expected strikes plus the cumulative probability per strike. Compare side-by-side: - Split mode — two panels, perfectly aligned outcome rows. - Overlay mode — one curve with the dominant tip in red/green per outcome, so you can see who wins at every value. - Difference mode — diverging bars showing exactly which outcomes shifted, plus a kill-probability lead callout. SYSTEMS COVERED Built for and tested with: - D&D 5e (and OneD&D) - Baldur's Gate 3 - Pathfinder - Diablo, Path of Exile, Last Epoch (multiplicative resistance, mixed damage types) - Anywhere weighted-RNG is the substrate. ZERO TRACKING The app collects no personal data on-device. No accounts, no cookies, no third-party trackers, no advertising, no analytics SDKs. The embedded reference content (Concepts and Games) loads from diceplots.com, which keeps aggregate-only event logs — no IP, no user-agent, no fingerprinting. Full policy in-app under More → Privacy, or at diceplots.com/privacy. OFFLINE BY DEFAULT The dice engine runs entirely on-device. Network access is only used to load the optional reference articles. You can compute distributions, compare rolls, and simulate dice without touching the network. OPEN ABOUT THE MATH Diceplots ships the same engine that powers diceplots.com. The Rust core is identical, the bindings are generated from one interface definition, and every probability is verified against a cross-platform corpus before each release. The numbers you see on Android, iOS, and the web are bit-identical because they come from the same library. The Concepts section walks through the math behind every readout — variance, kill probability, expected strikes — without simulation hand-waving. — Defensible Logic, Inc.