List of free, open source operating systems

Updated: May 20, 2023

  1. OpenBSD
  2. Linux
  3. FreeBSD
  4. NetBSD
  5. Dragonfly BSD
  6. Qubes OS
  7. Haiku
  8. Redox
  9. ReactOS
  10. AROS
  11. FreeDOS
  12. BASIC-DOS
  13. Blog series: Writing an OS in Rust
  14. skiftOS
  15. Tock
  16. Essence
  17. Subgraph OS
  18. osv.io
  19. axle OS
  20. Essence
  21. Barrelfish
  22. ToaruOS
  23. Mezzano
  24. House
  25. Minoca OS
  26. Kerla
  27. SOS
  28. PowerNex
  29. Interim OS
  30. KolibriOS
  31. MINIX
  32. RISC OS
  33. HelenOS
  34. GeckOS/A65 V2.0
  35. Serenity
  36. GNU Hurd
  37. Plan 9
  38. Harvey
  39. illumos
  40. AquilaOS
  41. NuttX
  42. Sculpt
  43. Biscuit
  44. Xv6