Which Linux distributions run in a browser
Why Ubuntu will not boot here, which distributions will, and how to pick one depending on what you want to do.
The first thing to get out of the way: the distribution you use on your laptop almost certainly will not boot here. Ubuntu, Fedora, Debian's default images and everything else mainstream stopped shipping 32-bit installers years ago, and the emulator underneath this site is a 32-bit machine. There is no workaround.
That sounds like bad news and mostly is not, because the distributions that *do* fit are the interesting ones anyway: small, fast, and built by people who cared about exactly how much a system needs to contain.
The requirements
- 32-bit x86 (i686 or older). Non-negotiable.
- Boots from BIOS, not UEFI.
- Fits in a few hundred megabytes of RAM. Anything asking for 2 GB is impractical.
- Does not need 3D, sound or a working network to reach a usable state.
What to pick
| If you want to… | Boot | Why |
|---|---|---|
| Use a real distribution with a package manager | Arch Linux | Actual pacman, gcc and python. Files stream over 9p, so it starts in seconds. See the Arch guide. |
| See a graphical desktop quickly | SliTaz or Tiny Core | A complete windowed desktop in around 50 MB, running entirely from RAM. |
| Watch a kernel boot with nothing around it | Buildroot | A bare bzImage with busybox and an editable kernel command line. No bootloader, no disk. |
| See something genuinely strange | NodeOS | A Linux kernel whose entire userland is Node.js — npm is the package manager. |
| Go as small as physically possible | ELKS | Linux rebuilt for 8086-class hardware. Multitasking UNIX on a processor from 1978. |
| Read a kernel you could actually finish | Tilck | Small enough to read end to end, yet binary-compatible with Linux — it runs unmodified Linux binaries. |
A note on "lightweight"
Distributions like Damn Small Linux and Tiny Core get described as lightweight, which undersells what is going on. They are not stripped-down versions of something bigger; they are the result of deciding, component by component, what a desktop actually requires. DSL famously fit a window manager, a browser, a spreadsheet and a terminal into 50 MB — not by compressing a normal system, but by choosing different pieces.
Booting one is a decent way to recalibrate your sense of how much of a modern system is actually necessary.