Open-source Chrome extension
Install it from the Chrome Web Store or build from GitHub. It lives inside Chrome, not as a standalone app.
AI web agent guide
Nano Browser
Nanobrowser is a powerful open-source Chrome extension for AI web automation. If you want the same agentic power inside a real browser—with workspaces, vertical tabs, and multi-model AI—Tabbit is the free alternative built for 2026.
AI-native agent browser
macOS & Windows · Free download
What it is
What is Nano Browser?
Nano Browser (Nanobrowser) is an open-source AI web agent that runs as a Chrome extension. It uses multiple specialized agents to plan, navigate, and execute web tasks locally in your browser.
Multi-agent system
A Planner agent breaks down tasks while Navigator agents interact with pages, letting workflows self-correct.
Bring your own API keys
Connect OpenAI, Anthropic, Gemini, Ollama, Groq, Cerebras, Llama, or any OpenAI-compatible provider.
Privacy-first, local execution
Credentials and session data stay in your browser, not on a remote automation cloud.
Limits of an extension
Why Nano Browser users look for an alternative
Nanobrowser is excellent for developers, but its Chrome-extension shape creates friction for everyday power users.
It is not a real browser
Extensions cannot redesign tabs, workspaces, or the omnibox. You still browse inside plain Chrome.
API keys and quotas to manage
You must bring, fund, and debug your own LLM keys before any agent can run.
No built-in workspace discipline
Without vertical tabs or project spaces, deep research sessions quickly become tab chaos.
Limited to Chromium browsers
If your workflow spans different environments, you are tied to Chrome or Edge.
Why Tabbit
The AI-native browser Nano Browser points toward
Tabbit delivers the same agentic promise—autonomous web research, form filling, and data aggregation—but as a full browser, not an add-on. That means the agent, the tabs, the workspaces, and the AI chat all share one surface.
You also skip the API-key setup. Tabbit gives you multi-model access out of the box, runs on macOS and Windows, and keeps every sensitive step behind an explicit approval.
- ●Full browser with built-in agentic AI
- ●Vertical tabs + project workspaces
- ●Multi-model AI without API key setup
- ●One-click import from Chrome, Edge, Safari
- ●Free download for macOS and Windows
What you get
Three reasons Tabbit succeeds where extensions stop
Agent mode inside a real browser
Agents run in isolated tab groups, read pages, fill forms, and report back—without leaving the browser context.
Workspace-native tab design
Vertical sidebar, smart grouping, and project workspaces keep research sessions scannable at any depth.
Skills + omnibox context
Save prompts and scripts as reusable Skills. Type @ in the omnibox to reference tabs, screenshots, or files.
Comparison
Nano Browser vs Tabbit
| Capability | Nanobrowser | Tabbit |
|---|---|---|
| Product form | Chrome extension | Full AI-native browser |
| Agent execution | Multi-agent, local-only | Agent mode with approval guardrails |
| LLM access | Bring your own API keys | Multi-model access included |
| Tab / workspace design | Uses default Chrome tabs | Vertical tabs + workspaces |
| Context reference | Page-based through extension | @-mention tabs, screenshots, files |
| Platform support | Chromium browsers only | macOS + Windows apps |
| Pricing | Free + your API spend | Free during public beta |
FAQ
People also ask about Nano Browser
What is Nano Browser?+
Nano Browser, also called Nanobrowser, is an open-source Chrome extension that acts as an AI web agent. It automates web tasks using multiple agents that run locally in your browser, and it supports many LLM providers via your own API keys.
Is Nano Browser a full browser?+
No. Nanobrowser is a Chrome extension, not a standalone browser. It automates web pages inside Chrome or Edge but does not replace the browser itself.
How do I download Nano Browser?+
You can install Nanobrowser from the Chrome Web Store or build it from its GitHub repository. If you want a full AI-native browser instead, download Tabbit for macOS or Windows from the official site.
What is the best alternative to Nano Browser?+
For users who want agentic web automation without managing API keys or staying inside Chrome, Tabbit is the strongest alternative. It is a full browser with built-in agents, workspaces, vertical tabs, and multi-model AI.
Does Nano Browser work without API keys?+
No. Nanobrowser requires you to connect your own LLM API keys. Tabbit, by contrast, includes multi-model access and does not require personal API keys during its free public beta.
Is Nano Browser open source?+
Yes. The Nanobrowser project is open source and available on GitHub. Tabbit is a separate, productized browser that is free to use during public beta.
Can Nano Browser manage tabs and workspaces?+
Not really. As an extension it relies on Chrome's default tab model. Tabbit offers native vertical tabs, smart grouping, and project workspaces designed for deep work.
Where should I download Tabbit?+
Use the official Tabbit domain for your region from the header or final CTA—international visitors use tabbitbrowser.com; mainland China visitors use tabbit-ai.com.
Ready for a browser that automates, not just an extension?
Download Tabbit free and run your first agent-assisted workflow with built-in approvals.