AI search & GEO

AI Browsers: What They Are and What They Mean for Your Website

ChatGPT Atlas, Comet and Gemini in Chrome already read pages and fill out forms for people. What they are, what changes for your site and what to fix, with OpenAI's own guidance and a real test of three AIs.

The Notablia editorial team

12 min read
Published October 27, 2026

An AI browser is a web browser with a built-in assistant that can read the page you have open, summarize it, compare it with other tabs and, in the most advanced ones, click and fill out forms for you. ChatGPT Atlas, Perplexity Comet and Gemini in Chrome are the best known, and for your business they mean one thing: people aren't the only ones visiting your website anymore, their agents are too.

In the US, "ai browser" gets about 8,100 searches a month and "chatgpt atlas" 40,500 (DataForSEO, October 2026). Almost everything Google shows is a list of browsers for users. This guide covers the other half: what an agent sees when it lands on your site and what to fix so it picks you.

It's AI search and GEO in its purest form: getting noticed by a visitor that ignores your design and reads your code.

On this page

What is an AI browser (and what it isn't)

It's a regular browser with an AI assistant inside that understands the open page and can act on it when you ask.

An AI browser is a program for browsing the internet that builds a language model into the interface itself. It reads the page in front of you, answers questions about it, compares tabs and, in agent mode, clicks, fills out forms and completes multi-step tasks with your permission.

What it isn't: a plugin, a search engine or a chatbot in another tab. In an AI web browser, the AI lives inside and sees what you see: your tabs, the open page and, if you let it, your logged-in session.

What is an agentic browser?

It's the kind that doesn't stop at summaries: it browses on its own. Type "get quotes from three plumbers in Austin who work Saturdays" and it opens sites, compares them and fills out the forms. OpenAI calls it agent mode; Google calls it auto browse.

AI browser vs. AI browser extension: what's the difference?

An AI browser extension adds a chat panel to the browser you already use, with limited access to what's on the page. An AI browser is built around the assistant, so it can work across tabs and, with your permission, act inside your sessions. More power, more access to your data.

Best AI browsers: ChatGPT Atlas, Comet, Gemini in Chrome and more

The three that matter are ChatGPT Atlas, Comet and Gemini in Chrome, with Edge, Dia, Opera and Brave rounding out the list.

Browser	Made by	What stands out
ChatGPT Atlas	OpenAI	ChatGPT in a sidebar, optional memories and agent mode on paid plans
Comet	Perplexity	Free assistant that compares tabs and runs multi-step tasks
Gemini in Chrome	Google	Gemini in a side panel; auto browse agent for US AI Pro and Ultra users
Microsoft Edge	Microsoft	Copilot built into the browser
Dia	The Browser Company	Chat in the address bar that knows your open tabs
Opera One and Opera Neon	Opera	Aria assistant in Opera One; Opera Neon, relaunched in 2025, runs tasks on its own
Brave	Brave	Leo assistant, built around privacy

The dates worth knowing: Atlas launched on October 21, 2025, for macOS. Comet arrived in July 2025 for Perplexity Max subscribers and went free in October 2025. Chrome's agent rolled out on January 28, 2026, for paying subscribers in the US. Dia browser comes from the team behind Arc.

Claude for Chrome: what it is and how it differs from an AI browser

Claude for Chrome, which Anthropic calls Claude in Chrome, is an extension, not a browser. You add it from the Chrome Web Store and it works inside the Chrome you already use. Per Anthropic's own page, it reads the pages you're signed in to, then clicks, types and fills out forms, including across several tabs. It's available on all paid plans.

On risk, you grant access one site at a time, and Claude asks before financial, personal or work-critical actions. Anthropic's FAQ admits its protections against prompt injection "aren't foolproof" and suggests skipping banking, health records and credentials. The rule is the same as for any agent: keep those accounts out of the session, as our FAQ below says.

For your site, Claude in Chrome is one more reader that has to understand and operate your page. The same steps apply: prices in text, real buttons, labeled fields. The test is cheap. If you have a paid plan, ask it to fill out your contact form and note where it stalls.

Dia browser and Arc: what happened to The Browser Company's browsers

Dia is the AI browser from The Browser Company, the team behind Arc. Its site offers it as a free download for macOS and Windows. Dia uses your open tabs and connected tools as context. It can build a morning brief from your calendar and inbox, or pull data from Slack, Notion or Teams into a report. You can also block trackers and switch memory off.

What about Arc? It hasn't vanished, but it's frozen. In May 2025, the company said Arc would enter maintenance mode and stop being actively developed; it still gets security updates. In September 2025, Atlassian agreed to buy The Browser Company for about $610 million in cash, and Dia became its main bet.

If you're starting from scratch, we wouldn't pick Arc. And as a site owner, Dia asks nothing special of you: it reads text, labels and buttons like the rest. If your form passes the steps below, it passes in Dia too.

What an AI browser changes for your website

It changes who reads your site: besides people and search engines, agents now read your code, fill out your forms and choose on the customer's behalf.

Picture an accounting firm in Chicago. A client used to open three websites and compare. With an agent, they type "find a CPA in Chicago who does small-business taxes for under $500 and book a call," and the browser does the rest. If your pricing lives in a PDF or your form is a puzzle, the agent moves on.

It's the same logic as Google AI Mode, one step further: there, AI cites you; here, it also acts. And it reads the page's accessibility tree: labels, roles and button text. OpenAI says so in its Publishers and Developers FAQ: Atlas uses ARIA tags, the same ones screen readers rely on, to understand page structure.

Does an AI agent respect your robots.txt?

Not always, and that's by design. OpenAI runs three bots: GPTBot (training), OAI-SearchBot (ChatGPT search) and ChatGPT-User (actions a person requests). For the last one, its docs say that because those actions are user-initiated, "robots.txt rules may not apply." For a refresher on setting each one, read our guide on what is robots.txt and how to configure it.

One detail almost nobody mentions: if you block GPTBot, OpenAI won't train on what Atlas reads from your site, even when the user opts in.

How to prepare your website for an AI browser agent, step by step

You prepare it like an accessible website: key information in plain sight, HTML that explains every element and forms nobody has to guess at.

Put buying information in text

Prices or ranges, timelines, service area and hours, in HTML. Nothing important hidden in images or PDFs.
Use real buttons and links

A button or link with clear text, like "Get a quote." A div with an icon is invisible to many agents.
Label every form field

Each field with its own label, the right type (email, tel, date) and the autocomplete attribute. Plus error messages that say what went wrong.
Add ARIA only where HTML falls short

Dropdowns, tabs and modals: roles, aria-label and states like aria-expanded. If a native element exists, use it first.
Remove pointless obstacles

Pop-ups that cover the form, mandatory sign-ups to see a price, extra steps. Every barrier is an exit for the agent.
Check your robots.txt and structured data

Decide what to do with GPTBot and OAI-SearchBot, and make sure your business or product markup matches what's on the page.
Test it with an agent

Ask an AI browser to complete your contact form and note where it gets stuck. That list is your to-do list.

Copy-paste prompts

Act as a browsing agent that needs to [request a quote / book / buy] on this page. Here is its HTML: [paste the code]. Walk me through which fields and buttons you can identify, which ones are unclear or ambiguous, and what you would change in the HTML to complete the task without errors.

ChatGPT Atlas and your website: what OpenAI asks site owners to do

OpenAI asks site owners for three things: proper ARIA labels, a clear decision on which bots get in, and tracking with its campaign tag.

What you want	What to do	Per OpenAI
Atlas's agent uses your site correctly	Roles, labels and states on buttons, menus and forms	WAI-ARIA best practices
Show up in ChatGPT answers	Allow OAI-SearchBot in robots.txt	Takes about 24 hours
Keep your content out of training	Block GPTBot	Also covers what's read through Atlas
Track clicks from ChatGPT	Look for utm_source=chatgpt.com in your analytics	ChatGPT adds it automatically

The caveat that saves you grief: bad ARIA makes accessibility worse. Accessibility consultant Adrian Roselli criticized OpenAI in October 2025 for framing ARIA almost like an SEO trick, and the W3C's first rule of ARIA still stands: if a native HTML element exists, use it.

And if your site has its own assistant, make sure it doesn't trap the agent. Before adding one, read what is a chatbot and how to set it up without getting in the way.

How to track AI browser visits

You track them in three layers: traffic that comes from AI chats, your server logs and what happens in your forms.

ChatGPT adds utm_source=chatgpt.com to its links, so Google Analytics shows it as the session source. Your server logs show GPTBot, OAI-SearchBot or ChatGPT-User. The third layer is the subtle one.

How can you tell an AI agent visited your site?

Often, not from analytics: when the agent works inside the user's browser, it usually looks like any other visit. The clues are in the outcome: forms submitted in seconds and every field filled in on the first try. Log them anyway. It's real demand, just with a middleman.

We tested it

Tested in October 2026ChatGPT (gpt-4.1-mini with search), Perplexity (sonar) and Gemini 3.8 Flash, via the DataForSEO API

We asked all three AIs the same question in the US, Spain and Brazil: what is an AI browser, and what should a small business change on its website so AI browser agents can use it?

Perplexity was the best in all three markets: labeled forms, visible information and no blanket blocking of agents. In Brazil, it was the only one to cite OpenAI's ARIA advice.
ChatGPT didn't search the web in any market: zero sources and textbook tips like "keyword-rich" meta titles.
Gemini recommended ReserveAction and OrderAction markup in the US and cited unofficial sites in all three markets, such as atlasbrowserai.com, which isn't run by OpenAI.

None explained how to track agent traffic. And on Google US, the top results for "ai browser" are mostly browser roundups, Reddit threads and app listings: none of them covers what changes for your website.

Frequently asked questions about AI browsers

Is Google Chrome an AI browser?

Partly. Chrome now ships with Gemini in a side panel that reads the page you have open and answers questions about it. Since January 28, 2026, Google AI Pro and Ultra subscribers in the US also get auto browse, an agent that completes tasks and asks before buying or posting anything. Without those features, Chrome is still a classic browser, which is why many people compare it with ChatGPT Atlas or Comet, where the AI is the center of the experience.

How do I get the ChatGPT browser?

The ChatGPT browser is called ChatGPT Atlas, and you download it from OpenAI's website. It launched on October 21, 2025, for macOS, so check OpenAI's site for other platforms before you plan around it. You sign in with your ChatGPT account. The browser itself is free, while agent mode, the part that clicks and fills out forms for you, launched as a preview for paid Plus, Pro and Business plans.

Is there a free AI browser?

Yes. Perplexity made Comet free for everyone in October 2025, on Windows and Mac, agent included. Microsoft Edge has Copilot built in at no cost, and ChatGPT Atlas is a free download, although its agent mode requires a paid plan. The real price is data: an AI browser sees everything you see. Before you switch, check what it stores and whether you can turn its memory off.

Are AI browsers safe?

Safe enough for reading and summarizing, riskier for acting. The main threat is prompt injection: hidden text on a web page that tries to hijack the agent's instructions, a risk OpenAI itself acknowledges. OpenAI says Atlas's agent can't run code or download files and pauses on sensitive sites, and Chrome's agent asks before buying or posting. Still, keep your bank, health and work accounts out of agent sessions, or run the agent logged out.

What is Perplexity Comet?

Comet is Perplexity's AI browser. It launched in July 2025 only for the $200-a-month Max plan and became free for everyone in October 2025, on Windows and Mac. Its assistant compares open tabs and completes multi-step tasks on websites, like checking prices or filling out forms. In our test, Perplexity was also the AI that best explained how to prepare a website for these agents, citing its own Comet help center.

What is ChatGPT Atlas?

ChatGPT Atlas is OpenAI's web browser, launched on October 21, 2025, for macOS. It puts ChatGPT in a sidebar that sees the page you're on, can remember what you browse if you turn on its memories, and has an agent mode that opens tabs and clicks for you. According to OpenAI, that agent can't run code or download files and asks for confirmation on sensitive sites such as banks.