YabYab, Yet Another Browser, is a free Mac browser that keeps everything from Arc (tabs down the side, spaces, folders, Split View) and gives your Claude or ChatGPT plan an agent that works in your signed-in tabs.
Zen is a free, open-source browser built on Firefox that brings Arc’s layout, tabs down the side with spaces, folders and Split View, to Mac, Windows and Linux.
The short answer
- if you miss Arc and want spaces, pins and folders kept, on a Mac
- if you already pay for Claude or ChatGPT and want it to work in your signed-in tabs
- if you want Claude Code, Codex or Cursor to drive a real browser over MCP
- if you want Arc’s layout, free and open source
- if you prefer Firefox’s engine and its add-ons
- if you want no AI in your browser at all
At a glance
Yab and Zen, side by side.
| What | Yab | Zen Browser |
|---|---|---|
| Made by | Serafim Korablev | Zen Browser team (open-source community project) |
| Status | Updated | Updated |
| Runs on | Mac | Mac, Windows and Linux |
| Phone app | Not yet | None; Zen says it has no plans for a mobile version |
| Price | Free; its AI runs on your own Claude or ChatGPT plan | Free and open source |
| AI | An agent that works in pages, on your Claude or ChatGPT plan | No AI |
| Driven by outside agents | MCP and a command line | No |
| Engine | WebKit | Gecko |
| Tabs down the side | Yes | Yes |
| Spaces | Yes | Yes |
| Split View | Yes | Yes |
| Extensions | Chrome Web Store | Firefox add-ons |
| Ad blocker | Built in | No |
| Open source | No | Yes |
Checked October 9, 2026 on each maker’s own pages, linked under Sources. Prices are per month, in US dollars.
Where they differ
What separates them, area by area. Where one plainly has more, it says who; where it comes down to taste, it says so.
AIYab leads
Only Yab has an agent that clicks, types and finishes tasks in your pages. Yab’s agent works in tabs of its own beside yours, signed in as you, on your Claude or ChatGPT plan; Send, Pay and Delete wait for your yes. Zen has no AI: Firefox’s AI features are switched off by default.
Agents like Claude Code and CodexYab leads
Yab can be driven over MCP and a command line, through yab mcp and the yab command, for Claude Code, Codex, Cursor and any MCP client. Zen has no MCP server or command line for outside agents.
Tabs and windowseven
Both have tabs down the side, spaces, Split View, folders in the sidebar and tabs that sleep.
PriceYab leads
Yab: Free; its AI runs on your own Claude or ChatGPT plan. Zen: Free and open source.
Where it runsZen leads
Yab runs on Mac. Zen runs on Mac, Windows and Linux. On a Mac, Yab needs macOS 15.4 or later and Zen needs macOS 10.15 or later. Yab has no phone app yet. Zen has no phone app: Zen says it has no plans for a mobile version.
Engine and extensionsa matter of taste
Yab is built on WebKit, the engine Safari uses; Zen on Gecko, Firefox’s engine. Yab takes extensions from the Chrome Web Store, Zen from Firefox’s add-ons.
Privacyeven
Yab has an ad blocker built in. Yab has no account and no server of ours between you and your sites; what your agent reads goes to Anthropic or OpenAI under your account. Zen has open code. Zen sends no telemetry or crash reports, by its privacy policy; optional sync keeps encrypted data on Mozilla’s servers.
Where Zen is better
Zen comes out ahead on where it runs. It is also the better pick if you:
- Want Arc’s layout, free and open source
- Prefer Firefox’s engine and its add-ons
- Want no AI in your browser at all
The catch with each
Real limits, from the makers’ own words and our own use.
Zen Browser
- Releases are still labeled beta
- No phone app, and none planned
- Firefox add-ons only, not the Chrome Web Store
- No ad blocker of its own beyond Firefox’s tracking protection
Yab, honestly
- Mac only: macOS 15.4 or later, no Windows, iPhone or Android
- New: first released in September 2026
- Its AI needs a Claude or ChatGPT plan; ChatGPT’s free plan may work with low limits
- WebKit, as in Safari: a site tested only in Chrome can misbehave
- Closed source
What changed lately
- September 25, 2026Yab: First release
- September 5, 2026Zen: Spaces, folders and tabs sync between devices with a Mozilla account (1.22b)
- February 28, 2026Zen: Live folders for GitHub issues, pull requests and RSS (1.19b)
- August 27, 2025Zen: Tab folders added (1.15b)
Questions
Is Yab free?
Yes. Free; its AI runs on your own Claude or ChatGPT plan.
Is Zen Browser free?
Yes. Free and open source.
Which has an AI agent, Yab or Zen?
Yab. Yab’s agent works in tabs of its own beside yours, signed in as you, on your Claude or ChatGPT plan; Send, Pay and Delete wait for your yes. Zen has no AI: Firefox’s AI features are switched off by default.
Which runs on Windows, Yab or Zen?
Zen does. Yab runs on Mac.
Do Yab and Zen have phone apps?
Yab has no phone app yet. Zen has no phone app: Zen says it has no plans for a mobile version.
More comparisons
- Yab Manual: Bringing in from another browser
- Yab Manual: Connecting Claude or ChatGPT
- Yab Manual: Extensions
- Yab Manual: Yab’s tools over MCP
- Yab Manual: Privacy
- Zen home page
- Zen download page (macOS universal, Windows, Linux; beta)
- Zen 1.23.2b release (macOS universal dmg; Info.plist minimum 10.15)
- Zen 1.23.1b release (Firefox 157.0.1)
- Zen license (MPL-2.0)
- Zen AI preferences (all off)
- Zen welcome flow (Firefox import wizard)
- Firefox import from another browser
- Zen 1.15b release (folders)
- Zen 1.19b release (live folders)
- Zen 1.22b release (sync)
- Zen 1.12.9b release (tab unloader uses Firefox tab discarding)
- Zen FAQ (no mobile plans, donations)
- Zen Workspaces
- Zen Split View
- Zen Extensions (addons.mozilla.org)
- Zen Privacy and Security (Firefox password manager, tracking protection)
- Zen privacy policy
- Firefox 157 system requirements
Yab, Yet Another Browser.
Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.