Overview

Atari800 is an emulator for Atari 8-bit computers and the Atari 5200 console. It suits people who want to run software across a broad range of Atari systems, especially those who need flexible disk, file, and controller support. Its wide hardware coverage comes with one important caveat: a BIOS is required.

Key features

Atari800 covers systems from the Atari 400 and 800 through the XL and XE families, as well as the XE Game System and 5200 SuperSystem. Its cycle-exact emulation of the 6502, NMI, POKEY, ANTIC, and GTIA makes it a substantial option for users seeking support for core Atari hardware components.

Disk support includes ATR, XFD, DCM, ATR.GZ, and XFD.GZ images, with up to eight emulated drives. The emulator can also load Atari executables and BASIC programs, emulate cassette tapes, and save files to the host computer through the H: device. This range is useful beyond game-disk use, though requiring a BIOS adds a setup dependency.

Real joysticks are supported, alongside emulated paddles, light pens, light guns, mice, trackballs, and other controllers. Controller remapping and save states add flexibility. Atari800 can save screen captures as PCX or PNG files and sound output as WAV. NetSIO and FujiNet support network SIO over UDP with configurable port settings.

Pricing

Atari800 is free: the Atari800 plan costs 0.00 USD per free and is freely distributable under GPL version 2, with source code available. There are no paid tiers, trial period, seat limits, or quotas to weigh against the free plan. That makes it a straightforward choice for cost-conscious users, but the BIOS requirement still applies.

Platforms

Atari800 supports Linux, Windows, macOS, and Android. Source code and binary packages are available through GitHub releases; Linux packages are also covered by Debian and Fedora instructions. The GitHub releases page lists v7.2.1, dated 2026/09/13, as a release fixing build errors.

The project is written in C and developed under GPL version 2. Questions, bug reports, and discussion go to its user mailing list, while bug reports and pull requests can be submitted through GitHub Issues. Atari800 is freely distributable, but no security certifications or compliance claims are made.

Who it's for

Atari800 is a strong fit for users who need one emulator for Atari 8-bit systems and the 5200, particularly those handling several disk-image formats, BASIC programs, cassette media, or varied controllers. It is less suitable for anyone unwilling or unable to obtain the required BIOS.

Pros and cons

Pro: Broad Atari system coverage spans the 400, 800, XL and XE models, XE Game System, and 5200 SuperSystem.
Pro: Support for multiple disk formats and up to eight drives pairs with executable, BASIC, cassette, and host-file workflows.
Pro: Real and emulated controller options, remapping, save states, and PCX, PNG, and WAV output cover varied use cases.
Con: A BIOS is required before use, adding a prerequisite to setup.

Alternatives

For Atari 5200 and 8-bit computer emulation on the same four operating systems, kat5200 is another free option. Choose Altirra if Windows-only support is acceptable; it is free under GPL and supports Windows 7 or later on x86/x64 or ARM64. For Atari 2600 emulation, Javatari offers online access, while Stella covers Linux, macOS, and Windows, with voluntary donations.

Virtual Jaguar is a free open-source emulator core for users prepared to use a libretro frontend such as RetroArch. BigPEmu offers a free emulator download with Windows and Linux builds. Gearlynx is another free alternative. Teller is an open-source universal secret manager for developers, not an Atari emulator.

Browse more options in Atari Emulators or Multi-System Emulators.

Verdict

Choose Atari800 if you want free, broad Atari 8-bit and 5200 emulation with extensive disk, file, and controller support across desktop and Android platforms. Its main drawback is the required BIOS, so users who cannot meet that prerequisite should look elsewhere.

	Atari800	OpenEmulator
Free plan	Yes	No
Free trial	No	No
Paid from	Free	—
Open source	No	No
Platforms	Android, Linux, macOS, Windows	macOS
Free plan	Yes	Yes
BIOS required	Yes	—
Supported systems	—	2
License	—	open-source

Atari800 vs OpenEmulator

Atari800

OpenEmulator