AI browsers: what they can really do.

An AI browser is a web browser with an agent built in. Besides answering questions about a page, it can act on the web for you: click, type, fill in forms and move between tabs. As of September 2026, the main options are Claude in Chrome, Gemini’s auto browse in Chrome, Browse with Copilot in Edge, Perplexity Comet and Opera Neon. OpenAI’s own browser, Atlas, has already shut down.

They are useful for research and routine web chores. They also make mistakes and can be hijacked by text hidden in the pages they read. So the settings you choose matter more than which brand you pick.

01What is an AI browser?

There are two designs. In the first, the agent lives inside the browser you already use and works with your logged-in accounts. Claude in Chrome, Gemini auto browse and Edge’s Browse with Copilot work this way. In the second, the agent runs a separate browser on the vendor’s servers and reports back. OpenAI’s cloud browser works like that, and Comet’s assistant can run tasks in a virtual cloud browser.

The first is more capable, because the agent can reach your email, calendar and shopping accounts. That is also what makes it riskier. Our guide to computer use agents explains how these agents see a page and decide where to click.

02The AI browsers you can use in September 2026

A few notes on each:

• Claude in Chrome became available on every paid Claude plan on August 26, 2026. It does not run on other Chromium browsers or on phones yet. By default it approves actions it judges safe, and you can switch that off.

• Gemini auto browse shows you its plan before it starts. It aims to confirm with you before it sends messages, submits forms or opens sensitive financial and health sites, and it may ask you to finish payments, accept terms or create accounts yourself. You can stop it, or take over and hand the task back.

• Browse with Copilot, formerly Copilot Actions, launched in May 2026, when Microsoft retired Edge’s Copilot Mode. It asks for supervision before buying, booking, sending email or deleting calendar events, and it cannot use your autofill, saved passwords or wallet.

• Perplexity Comet became free for everyone in October 2025, when Max subscribers also got a background assistant. It reached iPhone and iPad in March 2026.

• Opera Neon is a paid browser built around agents, including Neon Do for work across tabs, and it can connect tools through MCP.

OpenAI moved its agentic browsing into the ChatGPT desktop app, which has a built-in browser, plus a Chrome extension and a cloud browser. Dia, from The Browser Company, is an AI-first browser for knowledge work. Atlassian announced it would buy the company in September 2025.

If you want narrower control than any of these, building your own helper is simpler than it sounds. Our tutorial builds a Chrome extension with AI in about an hour.

03The AI browsers that shut down

1. October 2025OpenAI launches ChatGPT Atlas, its own AI browser
2. May 2026Google shuts down Project Mariner, its web-browsing agent experiment, and folds the technology into Chrome’s auto browse and its Gemini Spark agent
3. May 2026Microsoft retires Copilot Mode in Edge and launches Browse with Copilot
4. July 2026OpenAI says it will retire Atlas and move its agent features into the ChatGPT desktop app and a Chrome extension
5. August 2026Atlas is retired on August 9

The pattern is clear. Agents are moving into the browsers and assistant apps people already use, instead of asking them to switch. Comet, Neon and Dia are the standalone exceptions still going. If you pick a product today, favor one tied to a browser or app you would use anyway.

04What AI browsers do well, and where they struggle

05How fast and reliable are AI browsers?

Agents work one step at a time: read the page, decide, act, check. That makes them slow to watch. Vendors increasingly run tasks in the background instead, as Comet’s assistant and OpenAI’s cloud browser do, so you can do something else meanwhile.

Reliability is improving but not solved, and the vendors say so. Google’s help page states: “You’re responsible for Gemini’s actions during a task, including mistakes and unexpected results like purchases.” Microsoft warns that Copilot “may misinterpret instructions, make mistakes, or be affected by malicious hidden instructions on web pages.”

Benchmarks can also flatter. A 2025 study that tested web agents on 300 live tasks across 136 websites found earlier results were over-optimistic. For current scores on longer computer tasks, see the OSWorld 2.0 numbers in our computer use guide. Start with short tasks and check the result.

06The prompt injection problem

Prompt injection means text in a web page, email or calendar invite that the agent reads as instructions. An agent that browses while signed in to your accounts is exactly the target these attacks want. Prompt injection explained covers how it works and the history.

The 2026 record is sobering. In August, Zenity Labs showed zero-click hijacks of five agentic browsers: Claude in Chrome, Gemini in Chrome, Perplexity Comet, ChatGPT Atlas and Copilot in Edge. Malicious instructions hid in emails, calendar invites and web pages. Some vendors patched, while others called the findings intended functionality.

Vendors report progress on their own tests. Anthropic says that with its probes and safety classifier running, no attacks in its test set succeeded against Claude Sonnet 5, Opus 5 or Mythos 5, and 0.3% succeeded against Fable 5. Those are the vendor’s own tests on its own attacks. They show real progress, not a guarantee.

07The settings to use

Whatever you choose, set it up so a hijacked or confused agent can do little harm. The wider rules are in our guide to letting an agent use your computer safely.

08FAQ

Next, see how computer use agents work, or read prompt injection explained before you give an agent your accounts.