The short answer
OneTab is a good fit when you want a free extension that turns a crowded browser window into a list.
Tab Space is for work you expect to return to: sessions live outside browser extension storage, remain searchable over time and appear beside active tabs in the systemwide Browser Tab Switcher.
The difference that matters
| Need | OneTab | Tab Space |
|---|---|---|
| Save and close | Convert tabs into a browser-based list | Save windows as named sessions in a native Mac library |
| Find an open tab | Use the browser’s own tab switching | Press Option-Tab from any app and focus the exact browser, window and tab |
| Organize over time | Folders, search, notes, tasks and stars | Sessions, tags, notes, favorites, search, merge, split and optional AI organization |
| Protect the archive | Browser extension storage and manual export; current OneTab pages describe sync status differently | Native database, user’s own iCloud, automatic snapshots and multiple export formats |
| Cost | Free | Free for two sessions; $9.99 one-time Plus; optional Pro for multi-browser and unlimited AI |
Which workflow fits you?
You mainly want tabs gone
You need a free, simple list inside the browser and do not need a native Mac archive, scheduled backups or a systemwide switcher.
You want the context back
You keep research for months or years, use Apple devices, want data outside browser extension storage, or need to find active tabs across browsers.
Import your OneTab list
Export your saved list from OneTab. In the Tab Space dashboard, choose Import → Import OneTab and paste the text. Each group becomes a session you can rename, tag, back up and sync through iCloud.
Fact check
OneTab facts were checked against its official overview, Help and troubleshooting pages. Its homepage advertises encrypted cross-browser sync while Help still labels encrypted sync and backup “coming soon,” so this page does not assume either state.
Everything open and everything saved, in one search.
Download Tab Space free for Mac. No Tab Space account required.