List of free, open source operating systems

Updated: August 21, 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. Ares
  19. osv.io
  20. axle OS
  21. Essence
  22. Barrelfish
  23. ToaruOS
  24. Mezzano
  25. House
  26. Minoca OS
  27. Kerla
  28. SOS
  29. PowerNex
  30. Interim OS
  31. KolibriOS
  32. MINIX
  33. RISC OS
  34. HelenOS
  35. GeckOS/A65 V2.0
  36. Serenity
  37. GNU Hurd
  38. Plan 9
  39. Harvey
  40. illumos
  41. AquilaOS
  42. NuttX
  43. Sculpt
  44. Biscuit
  45. Xv6