For most of 2025, "AI browser" meant a new browser: Comet, Atlas, Dia. By September 2026 most AI browser agents run inside Chrome. Google puts Gemini inside Chrome itself, Anthropic ships Claude in Chrome as an extension, and OpenAI moved its agent into a Chrome extension and its desktop app after shutting down Atlas. This page tracks where the agents are and who can use them.
The Landscape, September 2026
| Agent | Delivery | Agent availability | Reach |
|---|---|---|---|
| Gemini in Chrome (auto browse) | Built into Chrome | Desktop auto browse since 2026-01-28 for US AI Pro and Ultra; Android since 2026-08-18 for US AI Pro and Ultra | Basic Gemini in Chrome reaches all eligible US Chrome users; auto browse is limited to paid tiers |
| Claude in Chrome | Chrome extension | Pilot Aug 2025, Max beta Nov 2025, Pro/Team/Enterprise Dec 2025, generally available on all paid plans from late Aug 2026 | Estimated 10-15 million Chrome Web Store users (third-party reports: about 9M in June, about 15M in September) |
| ChatGPT agent | Chrome extension, desktop app, cloud browser | Took over Atlas agent features on 2026-08-09 | Not disclosed |
| Perplexity Comet | Standalone browser | Desktop July 2025, Android Nov 2025, iOS March 2026 | Not disclosed; reached #3 overall on the US iOS App Store at its March launch |
Why Extensions and Built-In Agents Are Winning
No need to switch browsers. OpenAI named this as its reason for closing Atlas. An extension installs in seconds and keeps the user's logins, passwords, and bookmarks. A new browser has to replace all of them.
The user's logins come along. Agents that run in the user's own Chrome profile can act on sites the user is already signed into. Cloud agents have to log in from scratch, and many sites block them.
Chrome's reach. Chrome has an installed base in the billions. Gemini in Chrome doesn't need an install at all, which makes Google's potential reach the largest by a wide margin, even though auto browse is limited to paying US subscribers for now.
Limits on Current Usage
- Paywalls. Every agent above that can take actions requires a paid tier, except basic Comet features. Most users can ask these tools to summarise a page, but far fewer can have them act on it.
- Geography. Gemini's auto browse is US-only on both desktop and Android.
- Trust. Every vendor pauses before purchases and sensitive actions, and warns against using agents on banking or health sites because of prompt-injection risk. Claude in Chrome's store rating (about 2.8 of 5 in September, per listing reports) suggests reliability is still uneven.
Brand Visibility Implications
An agent running inside Chrome shows up in your analytics as Chrome. Your site gets agent visits whether or not you can tell them apart from human ones, and the agent judges your site on things a human skims past: whether prices are readable, whether stock status is clear, and whether forms can be filled without JavaScript getting in the way. See browser AI agents and brand visibility for the page-level patterns and the agentic browser wars for the standalone-browser history.
Methodology
Launch dates, availability, and policy come from vendor primary sources wherever one exists: the OpenAI newsroom and ad policies, the Google Marketing Live 2026 announcement, the Apple Newsroom, the OpenAI Help Center, and the Chrome blog. Pricing, penetration, and install counts are not published by the vendors and come from trade press and third-party trackers (Digiday, Marketing Dive, MacRumors, BGR, and Chrome Web Store listing reports). Those figures are shown as ranges and labelled as estimates. Figures are as of September 2026.
How Presenc AI Helps
Presenc AI logs AI crawler and agent traffic by user agent and behaviour, so you can separate agent sessions from human ones and see which pages agents complete tasks on and which they abandon.