Vault-Tec Labs

Screenshot from FOnline

The FOnline Engine is an multiplayer and singleplayer game engine. The engine is in no way connected to Interplay's Project V13 (Fallout Online), the official Fallout MMO. The FOnline Engine was created from scratch and supports original Fallout, Fallout 2, Fallout: Tactics, Arcanum and Baldur's Gate graphic and sound assets.

The development of FOnline (Engine) started in early 2004.

Official site -


On May, 2020, the FOnline Engine does on

SDK Release[]

On September 1, 2010, the FOnline SDK was released.

Open Source[]

On October 31, 2018, FOnline source code was released.

Licensed under MIT license - a short, permissive software license. Basically, you can do whatever you want. Also you may use the work commercially.

Constantly updated repository is accessible here -


  • Open Source under MIT license
  • Isometric graphics (Fallout 1/2/Tactics or Arcanum -like games)
  • Online mode with authoritative server
  • Singleplayer mode (work without distinguish between server and client sides)
  • Supporting of hexagonal and square map tiling
  • Perendered sprites for environment but with possibility of using 3D models for characters
  • Engine core written in C++17
  • Flexible scripting system with varies supporting languages:
    • Mono C# (modern and safe scripting)
    • Native C++ (for performance critical places)
    • AngelScript (engine legacy scripting support)
  • Cross-platform with target platforms:
    • Windows
    • Linux
    • macOS
    • iOS
    • Android
    • Web
    • PlayStation
    • UWP (PC, Mobile, Xbox)
  • Supporting of following asset file formats:
    • Fallout 1/2
    • Fallout Tactics
    • Arcanum
    • 3D characters in modern graphic formats
    • and more...

Games based on the FOnline Engine[]

FOnline: The Life After[]

The first game based on the FOnline engine was FOnline: The Life After. It was only developed in russian and english. The game is set in the year 2246 on the Fallout 2 worldmap.

FOnline: 2238[]

FOnline: 2238 was a Fallout game based on the FOnline engine, but the project has since been closed.  The game was set in the year 2238, 3 years before Fallout 2 starts and uses the Fallout 1 and 2 worldmap combined into one, allowing players to explore and adventure through the entire 'classic' Fallout world. It also includes an expansive system of professions and crafting items to promote a Player-based economy. The main feature of this game is the ability to enlist with existing canon organisations (such as the mighty Brotherhood of Steel, the up-and-coming NCR or the sinister Enclave), join a player-created faction or even form your own wasteland gang.

Fonline: Reloaded[]

FOnline: Reloaded is a reboot of FOnline 2238, striving to fix many of the issues that made FOnline 2238 frustrating for some. It promises improved PVP functionality, uncapped leveling, rare item accessibility, better quests and dungeons, and easier crafting. Its first test run should happen starting 8/31/2013.

FOnline: Ashes of Phoenix[]

FOnline: Ashes of Phoenixis a game based on FOnline engine, but unlike the other FOnline is set in a completely new area, that being the city of Phoenix, and has a completely new map. It is primarly focused on the various factions fighting over control of the city.

FOnline 2[]

This is the latest and most anticipated of all FOnline projects. Featuring hundreds of new features, a totally reworked crafting system, new vehicles and items, PvP and PvE quests, and the largest and friendliest english speaking community, it is sure to remain the premiere FOnline game. See, their forums.


It is possible to build new games with the FOnline engine, which are 100% independent from all Fallout content. Thanks to this, it is also possible to use the engine for commercial projects.

You can find more servers info here or

There are few FOnline-based games source which are free to use and allow create your own server, singleplayer game or play favorite server on localhost alone or with friends.

FOnline: 2238,29387.0.html

FOnline: The Life After

FOnline: Reloaded (1st session)

FOnline: Reloaded (2nd session)

External links[]