Pick Dia if
arc / The Browser Company users who want tab-aware chat and will pay for AI.
Read the Dia pageDia vs SigmaOS
Our take
Pick Dia if arc / The Browser Company users who want tab-aware chat and will pay for AI. Pick SigmaOS if mac users who will stay on Personal Free forever at $0 (unlimited workspaces, ad-blocker, limited Airis) while they open a first IcelandOffsite workspace, then Personal Pro at $20/month when they need unlimited Advanced Airis — not Personal Max $30 unless they need more LLM models and unlimited Look it up /
Best for
Dia A browser with tab-aware answers
SigmaOS A workspace browser you start at a public $
Free plan
Dia $0 · no AI. Profiles, tab groups, split-view, blocker, sync
SigmaOS $0 · forever. FAQ: “SigmaOS Personal is free for everyone and anyone, forever.” Card: unlimited workspaces, fast ad-blocker, Airis Assistant (limited)
Lowest paid
Dia Better Answers $10/mo
SigmaOS Personal Pro $20/mo
Next step up
Dia Usage top-ups $20
SigmaOS Personal Max $30/mo
Watch out
Dia Free has no AI
SigmaOS Unlimited Airis is paid
Last checked
Dia 2026-10-22 · diabrowser.com
SigmaOS 2026-10-23 · sigmaos.com
Which one, then?
Pick SigmaOS if
mac users who will stay on Personal Free forever at $0 (unlimited workspaces, ad-blocker, limited Airis) while they open a first IcelandOffsite workspace, then Personal Pro at $20/month when they need unlimited Advanced Airis — not Personal Max $30 unless they need more LLM models and unlimited Look it up / Interactive Summaries. Students and educators print 50% off Pro.
Read the SigmaOS page