What Is Proton on Steam Deck? (And How to Use It)
Proton is the reason the Steam Deck can run Windows games on Linux. Without it, your Steam library would mostly be empty on SteamOS. Here’s exactly what Proton is, how it works, and how to use it effectively.
What Is Proton?
Proton is a compatibility layer developed by Valve that lets Windows games run on Linux. It’s built on Wine (a Windows API translation layer) plus a collection of performance patches, shader compilation tools, and game-specific fixes that Valve and the community maintain.
When you install a Windows-only game on the Steam Deck, Proton intercepts the Windows API calls the game makes and translates them into Linux equivalents in real time. The game doesn’t know it’s running on Linux. It sees what it expects to see, runs its code, and outputs frames.
The result: thousands of Windows-only games work on SteamOS without you doing anything.
Proton vs Steam Play
You’ll see both terms used. Steam Play is the umbrella feature in Steam that enables running Windows games on Linux. Proton is the compatibility layer that Steam Play uses to make it work. Think of Steam Play as the button you press and Proton as the engine underneath.
Proton Versions: Which One to Use
Valve releases multiple versions of Proton simultaneously. Each version targets different compatibility goals:
| Version | Best For |
|---|---|
| Proton Stable (latest) | Most games, start here |
| Proton Experimental | Newer games not yet in stable; may have bugs |
| Proton GE (community) | Games with cutscene audio issues; broader codec support |
| Older versions (e.g. 7.0, 8.0) | Games that broke in newer Proton updates |
For 90% of games, use the default Proton version Steam Deck selects automatically. Only change it if a game has issues.
How to Change Proton Version for a Specific Game
If a game isn’t launching or has audio/visual issues, switching the Proton version often fixes it:
- Open Steam in Desktop Mode
- Right-click the game in your library
- Select Properties
- Click the Compatibility tab
- Check “Force the use of a specific Steam Play compatibility tool”
- Select a different Proton version from the dropdown
- Close and relaunch the game
In Gaming Mode, press the Steam button → highlight the game → press the gear icon → Properties → Compatibility. The same option is there.
What Is Proton GE?
Proton GE (Glorious Eggroll) is a community-maintained fork of Proton that includes patches and codecs Valve can’t ship in the official version for licensing reasons. The main addition is full video codec support, games with cutscene videos that show blank screens on official Proton often work correctly in Proton GE.
To install Proton GE on Steam Deck:
- Switch to Desktop Mode
- Open the Discover software store
- Search for ProtonUp-Qt and install it
- Open ProtonUp-Qt → Add version → select Proton-GE → Install
- Restart Steam
- The GE version now appears in the Compatibility dropdown for any game
How to Check If a Game Works with Proton
Before buying a game you’re unsure about, check ProtonDB. It’s a community database of game compatibility reports, each entry shows whether a game runs natively on Steam Deck, works via Proton, needs configuration tweaks, or is broken.
Ratings on ProtonDB:
- Native: Game has a Linux version, runs without Proton at all
- Platinum: Works flawlessly out of the box via Proton
- Gold: Works with minor tweaks (launch options, Proton version change)
- Silver: Works with significant workarounds
- Bronze: Runs but with notable issues
- Borked: Doesn’t run at all
Valve’s own Steam Deck Verified program covers the same ground but only for games they’ve officially tested on Steam Deck hardware.
Common Proton Issues and Fixes
| Problem | Fix |
|---|---|
| Game won’t launch | Try Proton Experimental or an older version |
| Cutscene videos are blank | Switch to Proton GE |
| Game crashes after a few minutes | Check ProtonDB for known fixes; try different Proton version |
| No audio | Try Proton Experimental; check if game needs Proton GE |
| Anti-cheat blocked | Game uses kernel-level anti-cheat, won’t work on SteamOS |
Games That Don’t Work with Proton
Proton can’t bypass kernel-level anti-cheat software. Games using EasyAntiCheat or BattlEye work if the developer enables the Linux/Proton version of those tools, but not all do. Warzone, VALORANT, and Apex Legends are examples of games that either don’t work or have limited support on SteamOS.
For those games, the ROG Ally X running Windows is the better handheld. See our Steam Deck vs ROG Ally X comparison for a full breakdown.
Proton and Non-Steam Games
You can use Proton for non-Steam Windows games by adding them as non-Steam shortcuts:
- In Steam Desktop Mode, click Games → Add a Non-Steam Game to My Library
- Browse to the .exe file
- Add it, then right-click → Properties → Compatibility
- Enable Steam Play and choose a Proton version
This works for GOG games, Epic Games titles, and any standalone Windows executable. Performance varies, Steam games get specific Proton patches and optimisations that non-Steam games don’t benefit from.
Bottom Line
Proton is what makes the Steam Deck viable as a gaming device. Without it, SteamOS would have a fraction of the game library. With it, you get access to the majority of the Steam catalogue on Linux hardware.
The default Proton settings work for most games. When they don’t, ProtonDB tells you what to change. Proton GE covers the remaining edge cases. For the ~5% of games that are genuinely incompatible due to anti-cheat, you’ll need Windows, which is why the ROG Ally X and Legion Go 2 exist.
Want to dig deeper? See our Steam Deck emulation guide and our Steam Deck tips and tricks for more ways to get more out of your device.
Proton is also what makes SteamOS work well on other handhelds. See our guide to installing SteamOS on the ROG Ally X, and our handheld gaming PC rankings for how Proton compatibility factors into buying decisions.