kitio.aiOpera One vs SigmaOS
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Opera One is completely free, while SigmaOS is freemium.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Opera AI sidebar assistant
- Tab Islands
- Workspaces
- Built-in ad blocker
- Sidebar music player
- Cross-device sync
- Workspaces
- Vertical tabs
- Tabs as tasks
- Split screen
- Lazy Search
- Airis AI companion
| Feature | Opera One | SigmaOS |
|---|---|---|
| Best for | Free desktop browser with built-in Opera AI and an ad blocker | Mac browser with workspaces, tabs as tasks and an AI companion |
| Category | Productivity | Productivity |
| Pricing model | Free | Freemium |
| Starting price | Free | See pricing page |
| Free plan | Yes, fully free | Yes |
| Made by | Opera | SigmaOS |
| Based in | Norway | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
|
|
Both offer: Workspaces.
Pricing compared
Opera One is completely free, while SigmaOS is freemium.
Free plan
Cheapest paid plan
Top plan
Free trial
Prices in USD, checked Oct 29, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
Opera One
- AI assistant included at no cost
- Ad and tracker blocking built in
- Good tools for heavy tab users
- AI features need an Opera account
- Sidebar extras can feel cluttered
- Less extension focus than Chrome
SigmaOS
- Free to download
- Clear tab organization by workspace
- AI answers in the page context
- Mac only
- Takes getting used to after Chrome
- Pricing for extras not shown
Which one should you choose?
Choose Opera One if you want:
- AI assistant included at no cost
- Ad and tracker blocking built in
- Good tools for heavy tab users
Watch out: ai features need an opera account.
Choose SigmaOS if you want:
- Free to download
- Clear tab organization by workspace
- AI answers in the page context
Watch out: mac only.
Opera One vs SigmaOS FAQ
What is the difference between Opera One and SigmaOS?
Opera One: Free desktop browser with built-in Opera AI and an ad blocker. SigmaOS: Mac browser with workspaces, tabs as tasks and an AI companion. Both are productivity tools.
Is Opera One or SigmaOS cheaper?
Opera One is completely free, while SigmaOS is freemium.
Do Opera One and SigmaOS have free plans?
Opera One: Yes, fully free. SigmaOS: Yes.
Who makes Opera One?
Opera One is made by Opera, based in Norway.
Who makes SigmaOS?
SigmaOS is made by SigmaOS, based in United States.
Which should I choose, Opera One or SigmaOS?
Choose Opera One if you value ai assistant included at no cost and ad and tracker blocking built in. Choose SigmaOS if you value free to download and clear tab organization by workspace.