YabZen 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.
Comet is Perplexity’s free Chromium browser for Mac, Windows, iPhone and Android, with Perplexity’s search and an assistant that can act on pages for you.
The short answer
- 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
- if you use Perplexity and want its search and agent in the browser
- if you want one AI browser on Mac, Windows, iPhone and Android
- if you want a free Chromium browser with an ad blocker built in
- 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
At a glance
Zen and Comet, with Yab beside them for a Mac.
| What | Zen Browser | Perplexity Comet | Yab |
|---|---|---|---|
| Made by | Zen Browser team (open-source community project) | Perplexity | Serafim Korablev |
| Status | Updated | Updated | Updated |
| Runs on | Mac, Windows and Linux | Mac, Windows, iPhone and Android | Mac |
| Phone app | None; Zen says it has no plans for a mobile version | iPhone, iPad and Android; on iPhone it syncs bookmarks and history with desktop Comet | Not yet |
| Price | Free and open source | Free; Comet Plus $5/month; Perplexity Pro $20/month or Max $200/month for more AI and agent use | Free; its AI runs on your own Claude or ChatGPT plan |
| AI | No AI | An agent that works in pages, on its own AI service | An agent that works in pages, on your Claude or ChatGPT plan |
| Driven by outside agents | No | No | MCP and a command line |
| Engine | Gecko | Chromium | WebKit |
| Tabs down the side | Yes | Not stated | Yes |
| Spaces | Yes | Not stated | Yes |
| Split View | Yes | Yes | Yes |
| Extensions | Firefox add-ons | Chrome Web Store | Chrome Web Store |
| Ad blocker | No | Built in | Built in |
| Open source | Yes | No | No |
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.
AIComet leads
Only Comet has an agent that clicks, types and finishes tasks in your pages. Zen has no AI: Firefox’s AI features are switched off by default. Comet’s assistant answers about pages and open tabs and can click, fill forms and navigate for you, asking before it acts.
Tabs and windowsZen leads
Zen has tabs down the side, spaces, Split View, folders in the sidebar and tabs that sleep. Comet has Split View, folders in the sidebar and tabs that sleep.
PriceComet leads
Zen: Free and open source. Comet: Free; Comet Plus $5/month; Perplexity Pro $20/month or Max $200/month for more AI and agent use.
Where it runsComet leads
Zen runs on Mac, Windows and Linux. Comet runs on Mac, Windows, iPhone and Android. On a Mac, Zen needs macOS 10.15 or later and Comet needs macOS 13 or later. Zen has no phone app: Zen says it has no plans for a mobile version. On the phone, Comet: iPhone, iPad and Android; on iPhone it syncs bookmarks and history with desktop Comet.
Engine and extensionsa matter of taste
Zen is built on Gecko, Firefox’s engine; Comet on Chromium, as Chrome is. Zen takes extensions from Firefox’s add-ons, Comet from the Chrome Web Store.
Privacyeven
Zen has open code. Zen sends no telemetry or crash reports, by its privacy policy; optional sync keeps encrypted data on Mozilla’s servers. Comet has an ad blocker built in. Comet keeps history, cookies and passwords on your device unless you sync; the assistant sends the page it needs to Perplexity, kept up to 30 days.
What their pages don’t lead with
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
Perplexity Comet
- Free use of the assistant is limited; more agent use is Pro at $20 or Max at $200
- No MCP server or command line from Perplexity for coding agents
- Researchers showed prompt-injection attacks on its agent in 2025 (CometJacking)
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 5, 2026Zen: Spaces, folders and tabs sync between devices with a Mozilla account (1.22b)
- August 4, 2026Comet: Ninth Circuit vacated the injunction Amazon won against Comet’s shopping agent
- March 18, 2026Comet: Comet for iPhone released
- February 28, 2026Zen: Live folders for GitHub issues, pull requests and RSS (1.19b)
- October 2, 2025Comet: Browser made free for everyone worldwide
- August 27, 2025Zen: Tab folders added (1.15b)
Questions
Is Zen Browser free?
Yes. Free and open source.
Is Perplexity Comet free?
Yes, with limits on its AI. Free; Comet Plus $5/month; Perplexity Pro $20/month or Max $200/month for more AI and agent use.
Which has an AI agent, Zen or Comet?
Comet. Zen has no AI: Firefox’s AI features are switched off by default. Comet’s assistant answers about pages and open tabs and can click, fill forms and navigate for you, asking before it acts.
Do Zen and Comet run on Windows?
Yes, both. Zen runs on Mac, Windows and Linux; Comet on Mac, Windows, iPhone and Android.
Do Zen and Comet have phone apps?
Comet does. Zen has no phone app: Zen says it has no plans for a mobile version. On the phone, Comet: iPhone, iPad and Android; on iPhone it syncs bookmarks and history with desktop Comet.
Is there a third option on a Mac?
Yab, Yet Another Browser, is free for the Mac: tabs down the side with spaces, folders and Split View, as in Zen; an agent in your signed-in tabs like Comet’s, on the Claude or ChatGPT plan you already pay for. Claude Code, Codex and any MCP client can drive it too. It runs on WebKit, the engine Safari uses, and takes Chrome extensions. It is Mac only, and new.
More comparisons
- 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
- Comet help: Operating System Requirements
- Comet help: What is Comet’s browser engine?
- Comet help: Browser features (split view, ad block, extensions, profiles)
- Comet help: Import data
- Comet help: Key settings (memory saver, tab groups)
- Comet help: Built-in password manager
- Comet help: Local data and device storage
- Comet help: Assistant privacy and data use
- Comet Quick Start Guide (Chrome import)
- Comet Assistant vs Agent
- Perplexity changelog Nov 14, 2025 (assistant asks approval before acting)
- Perplexity blog: Introducing Comet Plus ($5)
- Perplexity help: Perplexity Max
- Perplexity help: Local and remote MCPs
- App Store listing (iOS 18+, Pro $20, Max $200)
- TechCrunch: Comet now free (Oct 2, 2025)
- TechCrunch: Comet on Android (Nov 20, 2025)
- MacRumors: Comet on iPhone (Mar 18, 2026)
- Jones Day: Ninth Circuit vacates injunction (Aug 4, 2026)
- LayerX: CometJacking
- Community comet-mcp (not by Perplexity)
- Google Play: Comet: AI Browser & Assistant (updated Sep 24, 2026)
- Comet Help Center: Sync Between Devices
- Perplexity changelog: Comet iOS launch, pair mobile and desktop with device sync (Mar 27, 2026)
- Perplexity blog: Comet is now available on iOS
- Perplexity blog: Comet for Android is here
- MacStories: Comet for iOS review (sync chain, iPad version)
- 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
Yab, Yet Another Browser.
Free for the Mac. Arc’s sidebar, your own Claude or ChatGPT as the agent, Chrome extensions on WebKit.