Operating system showing Steam Deck specification Steam Deck runs
SteamOS version 3, based on the
Arch Linux operating system. While SteamOS had been previously developed for Steam Machines using
Debian Linux, Valve stated that they wanted to use a
rolling upgrade approach for the Deck's system software, a function Debian was not designed for, but which is a characteristic of Arch Linux. An
application programming interface (API) specific for the Steam Deck is available to game developers, allowing a game to specify certain settings if it is being run on a Steam Deck compared to a normal computer. Within the Steam storefront, developers can populate a special file depot for their game with lower-resolution textures and other reduced elements to allow their game to perform better on the Steam Deck; Steam automatically detects and downloads the appropriate files for the system (whether on a computer or Steam Deck) when the user installs the game. The version of Steam on the Deck otherwise supports all other functions of Steam, including user profiles and friends lists, access to game communities, cloud saving, Steam Workshop support, and the Remote Play feature. Remote Play allows the Steam Deck to be used as a controller for a game running on a computer, providing additional control options beyond traditional keyboard and mouse or common controller systems. Otherwise, games that do not take advantage of the Steam Deck API have the handheld's controller input automatically converted for them. For example, the touch-sensitive controllers on the Deck translate input appropriately for games that typically rely on
keyboard and mouse controls.
Games The Deck displays compatible games from the Steam storefront. Games developed for Linux run natively, however, the SteamOS software also includes support for
Proton, a compatibility layer that allows games developed for
Windows to be played on the Linux-based SteamOS. According to ProtonDB, a community-run database that compiles information on game compatibility of Steam games within Linux using Proton, several of Steam's more popular game releases were not yet compatible with Proton primarily due to anti-circumvention and
anti-cheat controls or
digital rights management (DRM). Valve stated they were working with vendors of these middleware solutions to improve Proton support while also encouraging Linux-specific versions to be developed.
Epic Games' Easy Anti-Cheat, one of the more popular anti-cheat options for developers, was made available for macOS and Linux systems in September 2021, which Epic stated that developers could easily transition for the Proton layer. Valve worked with Epic over the end of 2021 to make the transition of Easy Anti-Cheat to Proton simple for developers. Another popular anti-cheat solution,
BattlEye, also affirmed their software was ready to work with the Proton layer and only required developers to opt-in to enable it. Valve stated that in testing games otherwise currently available on Linux or compatible with the Proton layer, they had yet to find a game that failed to meet a minimum 30 frames-per-second performance on the handheld, a performance metric comparable to the consoles of the
eighth generation. The Proton layer includes support for AMD's upscaling technology
FidelityFX Super Resolution (FSR); while Proton also supports Nvidia's
DLSS upscaling solution, it is not compatible with the Deck. Due to potential confusion on game compatibility, Valve introduced a process in October 2021 by which they brought in additional staff to review games on Steam to make sure a game is fully playable on the Steam Deck. Games that are confirmed to be compatible with the Steam Deck, including those with Proton and any middleware DRM solutions, that by default meet minimum performance specifications, are marked as "". Games that may require some user tinkering with settings, such as having to use a system control to bring up the on-screen keyboard, are tagged as "Playable". Another category, "Unsupported", are games that Valve has tested to not be fully compatible with the Steam Deck, such as VR games, or games using Windows-specific
codecs that have not yet been made compatible with Proton or software apps. These ratings are to change over time as both the Steam Deck software improves as well as updates made by developers to games to improve compatibility with the Steam Deck software. By 2025, several other portable gaming computers had been released, with Valve preparing SteamOS to be used as the operating system for these devices. As part of a May 2025 update, Valve included a subset of the Steam Deck compatibility system to aid users on these alternate devices to help with identifying compatible games. Users download games onto the Steam Deck to store on either the internal storage or SD card, each storage device treated as a separate Steam Library for games. This allows SD cards with different Steam Libraries to be swapped in and out. Valve is exploring the ability to pre-load games on an SD card outside of the Deck, such as through a personal computer. The ability to download games onto the Steam Deck from a local network Steam installation was added in February 2023. While the Deck was designed for playing games on the
Steam storefront, desktop mode allows for installation of third-party storefronts like
Epic Games Store,
Ubisoft Connect, or
Origin. It is possible to replace SteamOS with a different operating system entirely or set up
multi-booting. Newell stated that Valve would support Microsoft in bringing
Xbox Game Pass to Steam and Steam Deck if they want that route. With the system's open nature, users have also been able to add
emulators to run games that users own from other consoles or computer systems.
Desktop interface and third-party utilities The Deck's operating system can also be launched into desktop mode, which uses the
KDE Plasma desktop environment with an immutable file system. A range of third-party software tools have been developed to bring additional utility to the device, typically installed through the desktop mode on the deck. Examples include SteamOS
plugin loader Decky,
emulation manager EmuDeck and the batocera.linux distribution. The Steam Deck was used as a remote control for animatronics at
Walt Disney World. It was also used for remote-operated gun turrets by Ukrainian forces defending positions during the
Russian invasion of Ukraine. ==Release==