List of Javascript based virtual machines running in browser

List of in-browser VMs.md

These are VMs running built with JavaScript/WASM allowing you to run an operating system within your browser, all client side.

Emulators

VMs

1. https://copy.sh/v86/
2. https://webvm.io/
3. https://bellard.org/jslinux/
4. https://jamesfriend.com.au/pce-js/ (https://github.com/jsdf/pce)
5. https://www.pcjs.org/ (lots of hardware and OSes) (https://github.com/jeffpar/pcjs)

Operating systems

Mac OS

1. https://infinitemac.org/ (https://blog.persistent.info/2023/03/infinitemac-dot-org.html)
2. https://jamesfriend.com.au/projects/basiliskii/BasiliskII-worker.html
3. https://jamesfriend.com.au/pce-js/pce-js-apps/

https://oldweb.today/ seems to do some of this as well.
https://infinitemac.org/ (per your HN comment)

https://software.inc/

https://schierlm.github.io/OberonEmulator/