Yab

Yab vs BrowserOS

We make Yab, so read it as our side.facts checked Oct 9 ↓

Yab, 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.

BrowserOS is an open-source Chromium agent browser for Mac, Windows and Linux. Its agent runs on the AI you connect: an API key, a ChatGPT or Copilot plan, Claude Code or Codex, or a local model.

The short answer

Pick Yabours
  • 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
Pick BrowserOS
  • if you want an open-source agent browser on your own AI keys or local models
  • if you want Claude Code, Codex or Cursor to drive a signed-in browser over MCP
  • if you use Linux

At a glance

Yab and BrowserOS, side by side.

Yab vs BrowserOS
WhatYabBrowserOS
Made bySerafim KorablevFelafax, Inc.
StatusUpdatedUpdated
Runs onMacMac, Windows and Linux
Phone appNot yetNone; desktop only, and no Android plans as of May 2026
PriceFree; its AI runs on your own Claude or ChatGPT planFree and open source; you pay your own AI provider
AIAn agent that works in pages, on your Claude or ChatGPT planAn agent that works in pages, on its own AI or yours
Driven by outside agentsMCP and a command lineMCP and a command line
EngineWebKitChromium
Tabs down the sideYesYes
SpacesYesNo
Split ViewYesYes
ExtensionsChrome Web StoreChrome Web Store
Ad blockerBuilt inNo
Open sourceNoYes

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.

AIa matter of taste

Both have an agent that works 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. BrowserOS’s agent, in the new tab and side panel, clicks, types, fills forms and pulls out data, on the AI you connect.

Agents like Claude Code and Codexeven

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. BrowserOS can be driven over MCP and a command line, through a built-in MCP server with one-click setup for Claude Code, Codex and Cursor, and a command line.

Tabs and windowsYab leads

Yab has tabs down the side, spaces, Split View, folders in the sidebar and tabs that sleep. BrowserOS has tabs down the side, Split View and folders in the sidebar.

PriceBrowserOS leads

Yab: Free; its AI runs on your own Claude or ChatGPT plan. BrowserOS: Free and open source; you pay your own AI provider.

Where it runsBrowserOS leads

Yab runs on Mac. BrowserOS runs on Mac, Windows and Linux. On a Mac, Yab needs macOS 15.4 or later. Yab has no phone app yet. BrowserOS has no phone app: desktop only, and no Android plans as of May 2026.

Engine and extensionsa matter of taste

Yab is built on WebKit, the engine Safari uses; BrowserOS on Chromium, as Chrome is. Both take extensions from the Chrome Web Store.

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. BrowserOS has open code. BrowserOS sends prompts and pages only to the AI you connect, or keeps them local with Ollama or LM Studio; it sends anonymous usage analytics.

Where BrowserOS is better

BrowserOS comes out ahead on price, where it runs. It is also the better pick if you:

  • Want an open-source agent browser on your own AI keys or local models
  • Want Claude Code, Codex or Cursor to drive a signed-in browser over MCP
  • Use Linux

The catch with each

Real limits, from the makers’ own words and our own use.

BrowserOS

  • No built-in model since version 0.51: connect a provider before the agent works
  • Its own docs say local models are too weak for agent tasks
  • Before 1.0 and changing fast: Skills and Memory were pulled in June 2026
  • No phone apps

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

  • October 5, 2026BrowserOS: Built-in model and account sign-in removed; Chromium 155 (0.51.0)
  • September 25, 2026Yab: First release
  • June 17, 2026BrowserOS: Claude Code and Codex built into the agent; Skills and Memory removed (0.46.0)
  • March 9, 2026BrowserOS: Vertical tabs became the default (0.42.0)

Questions

Is Yab free?

Yes. Free; its AI runs on your own Claude or ChatGPT plan.

Is BrowserOS free?

Yes. Free and open source; you pay your own AI provider.

Which has an AI agent, Yab or BrowserOS?

Both. 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. BrowserOS’s agent, in the new tab and side panel, clicks, types, fills forms and pulls out data, on the AI you connect.

Which runs on Windows, Yab or BrowserOS?

BrowserOS does. Yab runs on Mac.

Do Yab and BrowserOS have phone apps?

Yab has no phone app yet. BrowserOS has no phone app: desktop only, and no Android plans as of May 2026.

More comparisons

BrowserOS vs DiaBrowserOS vs CometBrowserOS vs AtlasBrowserOS vs Opera NeonBrowserOS vs ChromeBrowserOS vs SafariBrowserOS vs EdgeBrowserOS alternatives
Sources, read October 9, 2026. Something out of date? Write to hello@serafimlabs.io and we fix it.

Yab, Yet Another Browser.

Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.

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