"Playable in your browser" covers at least four different things, and they behave differently when you open them. Knowing which one you are looking at explains most of the confusion around this whole category, including why some links ask for your own game files and others start instantly.
The four kinds of browser port
Native port or rewrite
The game's code is rewritten for the web in JavaScript or WebGL. It starts instantly, needs nothing from you, and often loses some original behaviour along the way.
Decompilation build
Fans reverse-engineer the original game into readable source, then rebuild it for the browser. Very faithful, but it often expects assets from a copy you own.
Clean-room reimplementation
The engine is rebuilt from scratch with free replacement assets. Nothing commercial is used, so it runs without you supplying anything, at the cost of different art and audio.
Emulation
A full emulator runs the original machine's code in the browser. Highest fidelity, heaviest to load, and usually the category most sensitive to copyright complaints.
Why some entries ask for your own game files
Decompilation builds and emulators usually ship the engine but not the content. The engine is the community's work; the levels, textures and audio are still the publisher's. That is why a project can be perfectly legitimate and still ask you to import a game.tar.gz built from your own copy.
Where the line is
Converting files from a game you own is the normal, expected workflow for these projects. Downloading somebody else's game files is not, and it is the single fastest way to get a project taken down. Several entries in this directory have already disappeared or changed address for exactly that reason.
Why links break so often
These are hobby projects running on free hosting, personal domains and community infrastructure. A project can vanish because its domain lapsed, its free tier ran out, or it received a legal notice. The GTA 5 entry in our directory is a good example: the only surviving copy is a web archive, and an archived page is not the same as a working game.
This is also why we show a status note on every page and withhold the launch button on entries whose destination no longer matches the name.
Which kind should you pick?
| If you want | Look for | Entry type |
|---|---|---|
| Something to try in ten seconds | Native ports and clean-room builds | Ready to start |
| Maximum fidelity to the original | Decompilation builds or emulation | Bring your own files |
| Nothing legally grey at all | Clean-room builds and freeware releases | Ready to start |
| Multiplayer with other people | Projects with their own servers | Check setup first |
How our two collections differ
The From the list collection is the 25 projects shared by @RadiantOpti on 8 October 2026, including the ones with broken or mismatched destinations. The wider library is everything we added afterwards: DOS classics, open-source engines, emulation builds and clean-room reconstructions that fit the same idea even though they were not in the original graphic.
Filter the directory by collection to see each group, or read how to use the list if you want the short version.
Browse the directory
Every project, with a screenshot, its real destination and what it needs before it will run.