Free & Open Source Simulation Games
256 free, open-source simulation games — real clones and remakes you can download, inspect the source of, and modify. Not just free to play: the code itself is open.
Sporadic
Clone of SimCity
3d.city renders a live city simulation in full 3D via WebGL2 or WebGPU in the browser, using Three.js and the micropolisJS engine.
Active
Clone of Factorio
An open-source automation tower defense RTS in Java, for desktop, Android and iOS.
Platforms:WindowsLinuxOSX
Stars28,996
Updated1 month ago
LicenseGPL-3.0
Release2017
Genre: Simulation
Theme: —
Active
Clone of RollerCoaster Tycoon
An open-source re-implementation of RollerCoaster Tycoon 2 with modern platform support, higher limits and co-op multiplayer.
Platforms:WindowsLinuxOSX
Stars16,227
Updated1 month ago
LicenseGPL-3.0
Release2014
Genre: Simulation
Theme: Management
Active
Clone of Transport Tycoon
A free, actively developed remake and expansion of Transport Tycoon Deluxe with multiplayer and in-game mod downloads.
Platforms:WindowsLinuxOSX
Stars8,264
Updated1 month ago
LicenseUnknown
Release2018
Genre: Strategy
Theme: Management
Halted
Original game image
Original game imageClone of SimCity
Citybound is an independently developed, Patreon-funded open-source city-builder emphasizing realism and fine-grained simulation detail.
Platforms:Web
Stars8,163
Updated3 years ago
LicenseAGPL-3.0
Release2016
Genre: Simulation
Theme: Management
Active
Clone of Escape Velocity
Endless Sky is a sandbox 2D space trading and combat game inspired by Elite and Escape Velocity, developed for a decade by volunteers.
Platforms:WindowsLinuxOSX
Stars7,559
Updated1 month ago
LicenseGPL-3.0
Release2015
Genre: Action
Theme: —
Active
Clone of Powder Game
A free, open-source 2D physics sandbox simulating pressure, heat, gravity, and countless material interactions.
Platforms:WindowsLinuxOSX
Stars5,314
Updated2 months ago
LicenseGPL-3.0
Release2010
Genre: Simulation
Theme: —
Halted
Clone of SimCity 2000
An unfinished browser-based SimCity 2000 remake in JavaScript and Phaser 3 that can import and view cities but not simulate them.
Active
Clone of Theme Hospital
CorsixTH is a reimplementation of Theme Hospital for modern systems, adding 4K support, a map editor, and 20+ language translations.
Platforms:WindowsLinuxOSX
Stars4,558
Updated1 month ago
LicenseUnknown
Release2013
Genre: Strategy
Theme: Management
Active
Clone of Space Station 13
An open-source remake of SS13 built on a custom C# engine, with heavily moddable community servers.
Active
Clone of Spore
An open-source evolution sim where you guide a species from a single cell through mutation-driven natural selection.
Platforms:Windows
Stars3,706
Updated1 month ago
LicenseUnknown
Release2012
Genre: Simulation
Theme: Sci-Fi
Active
Clone of Caesar III
Julius is an open-source reimplementation of Caesar III reproducing the original's logic and save compatibility, with widescreen support.
Platforms:WebWindowsLinux
Stars3,375
Updated1 month ago
LicenseAGPL-3.0
Release2017
Genre: Simulation
Theme: Management
Active
Clone of Powder Game
A browser-playable falling-sand simulation in Rust/WebAssembly and WebGL, letting players create, share, and fork creations.
Archived
Original game image
Original game imageClone of Space Engineers
Keen Software House's archived release of Space Engineers' official source code, requiring an owned Steam copy of the game to build.
Active
Clone of Jones in the Fast Lane
An open-source engine reimplementation that lets classic point-and-click adventures and RPGs run on modern platforms.
Platforms:WindowsLinuxOSX
Stars2,811
Updated1 month ago
LicenseGPL-3.0
Release2011
Genre: Simulation
Theme: —
ActiveOriginal game image
Original game imageClone of SimCity
A free, open-source retro pixel-art city-builder with a custom SDL2 isometric engine in C++; core building mechanics are still planned.
Platforms:WindowsLinuxOSX
Stars2,160
Updated2 months ago
LicenseGPL-3.0
Release2018
Genre: Simulation
Theme: Management
Active
Clone of Caesar III
A fork of the Julius Caesar III re-implementation adding new customizable gameplay, actively developed for Windows, Linux, macOS, and more.
Platforms:Web
Stars2,082
Updated1 month ago
LicenseAGPL-3.0
Release2020
Genre: Simulation
Theme: Management
Active
Active
Clone of Chris Sawyer's Locomotion
A complete C++ re-implementation of Chris Sawyer's Locomotion, aiming to improve it the way OpenTTD improved Transport Tycoon.
Platforms:WindowsLinuxOSX
Stars1,904
Updated1 month ago
LicenseMIT
Release2018
Genre: Strategy
Theme: Management
Active
Clone of Black & White
An open-source C++ reimplementation of Lionhead's Black & White that runs on the original game's assets.
Platforms:WebWindowsLinux
Stars1,560
Updated3 months ago
LicenseGPL-3.0
Release2018
Genre: Simulation
Theme: Fantasy
Active
Original game image
Original game imageClone of Animal Crossing
A native PC port of Animal Crossing for GameCube, built on the ac-decomp decompilation with an OpenGL 3.3 layer.
Stars1,468
Updated3 months ago
LicenseUnknown
Release2026
Genre: Simulation
Theme: —
Active
Clone of Tabletop Simulator
An open-source, physics-driven 3D tabletop sandbox built with Godot, with free online multiplayer and no sign-up.
Platforms:WindowsLinuxOSX
Stars1,456
Updated2 months ago
LicenseMIT
Release2020
Genre: simulation video game
Theme: —
Active
Clone of Animal Crossing
A decompilation of the USA revision of Animal Crossing for GameCube, still in development and requiring your own disc image.
Active
Clone of BeamNG.drive
An open-source soft-body vehicle physics sandbox with online multiplayer, simulating cars, trucks, boats, and aircraft.
Platforms:WindowsLinux
Stars1,245
Updated2 months ago
LicenseGPL-3.0
Release2014
Genre: Simulation
Theme: —
SporadicOriginal game image
Original game imageClone of SimCity
The GPL source release of Micropolis, the open-source SimCity, kept for historical versions of the code.
Platforms:WindowsLinuxOSX
Stars1,103
Updated9 months ago
LicenseUnknown
Release2015
Genre: Simulation
Theme: Management
Active
Clone of Dungeon Keeper
KeeperFX is an open-source expansion and remake of Dungeon Keeper for modern Windows, requiring the player's own original game files.
Active
Clone of The Sims Online
FreeSO is a MonoGame reimplementation of The Sims Online, now serving mainly as an engine base for other TSO servers.
Platforms:Windows
Stars976
Updated1 month ago
LicenseMPL-2.0
Release2015
Genre: Simulation
Theme: Management
Archived
Clone of Sea Dogs: To Each His Own
The open-source engine behind the Sea Dogs, Pirates of the Caribbean, and Age of Pirates games, now archived and community-maintained.
Platforms:Windows
Stars898
Updated3 years ago
LicenseGPL-3.0
Release2020
Genre: Action
Theme: —
Active
Clone of Artemis: Spaceship Bridge Simulator
EmptyEpsilon is an open-source game that began as an Artemis Spaceship Bridge Simulator clone but has since diverged with new features.
Platforms:WindowsLinuxAndroid
Stars869
Updated2 months ago
LicenseGPL-2.0
Release2014
Genre: Simulation
Theme: Sci-Fi
Active
Clone of Artemis: Spaceship Bridge Simulator
An open-source, Artemis-inspired multiplayer spaceship bridge simulator for Linux with Lua-scripted missions.
Active
Clone of Space Station 13
A free multiplayer RPG remake of the cult-classic Space Station 13, rebuilt outside the original BYOND engine.
Halted
Active
Active
Clone of SimCity
A modernized continuation of classic LinCity, a city-building sim where you build a sustainable city or evacuate everyone by spaceship.
Platforms:WindowsLinux
Stars632
Updated1 month ago
LicenseGPL-2.0
Release2015
Genre: Simulation
Theme: Management
Active
Clone of Freelancer
A C# and OpenGL reimplementation of Freelancer for Windows and Linux, requiring an existing Freelancer installation to run.
Halted
Clone of SimTower
An unfinished, unplayable open-source C++ remake of SimTower that needs the original game's SIMTOWER.EXE to run.
Platforms:WindowsLinuxOSX
Stars591
Updated7 years ago
LicenseGPL-2.0
Release2010
Genre: Simulation
Theme: Management
Halted
Clone of 北京浮生记
The official source code (version 1.2.2) for Beijing Fushengji, originally compiled with Visual C++ 6.0 on Windows XP.
Active
Clone of Pharaoh
A reimplementation of the Pharaoh game engine for modern systems, forked from the Julius/Augustus project and retargeted at Pharaoh.
Platforms:WebWindowsLinux
Stars509
Updated1 month ago
LicenseAGPL-3.0
Release2023
Genre: Simulation
Theme: Ancient History
Sporadic
Clone of Dungeon Keeper
An open-source dungeon-building RTS inspired by Dungeon Keeper, now mostly archived in favour of the OpenDungeonsPlus fork.
Platforms:WindowsLinux
Stars503
Updated1 year ago
LicenseUnknown
Release2014
Genre: Simulation
Theme: Horror