DragonDice is a small utility library that helps with the simulation and statistical evaluation of actions in the Dungeons & Dragons roleplaying game, specifically using the 5th edition of the rules as described in the Systems Reference Document.

In addition to the core library, a Telegram bot exposes the functionality for interactive use.


You can install the DragonDice library via NuGet or use the DragonDice Bot interactively.

To build DragonDice from source you will need an F# 4.5 compiler (or newer) and a .NET development environment. The .sln and .fsproj files in the source directories should be understood by .NET Core command line tools, MSBuild or IDEs such as VSCode, VisualStudio, or Rider.


Here's a brief example for using the DragonDice library:

#r "Murphy.DragonDice"
open System
open Murphy.DragonDice
open Murphy.DragonDice.UnitSystem

let chr = Character(Name = "Joe Sixpack", Race = "Human")
chr.Abilities <- EnumMap [
  Ability.Dexterity,      17
  Ability.Constitution,   12
  Ability.Intelligence,   20
  Ability.Charisma,       16
chr.Proficiencies <- chr.Proficiencies.With [
  Skill.Acrobatics,        1
  Skill.SleightOfHand,     1
  Skill.Arcana,            1
  Skill.Perception,        1
chr.AddLevel(Profession.Sorcerer, count = 4)

let chk = chr.GetCheck(Ability.Dexterity, Difficulty.Easy)
Check.estimate chk
|> printfn "estimate -> %A"

let rng = Random()
Check.simulate rng chk
|> printfn "simulate -> %A"


DragonDice is licensed under the Apache License, Version 2.0. Refer to the NOTICE for licenses of third-party dependencies.