One of the four AI web browsers we sat down to compare for this piece doesn’t exist any more. OpenAI switched off ChatGPT Atlas on 9 August 2026, not even ten months after it launched, and folded whatever people actually used into a desktop app and a browser extension instead. That’s the story of AI web browsers in one sentence: big launches, fast pivots, and a genuine question mark over whether any of this is ready for someone who just wants to check their bank balance without getting scammed.
The pitch is seductive. Instead of a search box, you get an assistant sitting in the browser itself, one that can read what’s on the page, summarise a thread of emails, compare three open tabs of flights, or, in the more ambitious versions, actually click the buttons and fill in the forms for you. Perplexity calls it Comet. Microsoft calls it Copilot Mode. Google’s version, tucked into Chrome, is Gemini with a feature called Auto Browse. We’ve used all three enough now to have a view on which bits are genuinely useful, which bits are marketing, and where the real risk sits.
What actually makes a browser agentic
It’s worth separating two very different things that get lumped under the same “AI browser” label. The first is a chat sidebar: it reads the page you’re on, answers questions about it, drafts a reply, translates something. Useful, low-risk, and honestly not that different from opening a chatbot in another tab. The second is an agent, something that can take actions inside your logged-in sessions on your behalf: clicking, typing, submitting, sometimes buying.
That second category is where the interesting claims live, and where the trouble starts. We’ve written before about how AI agents actually complete tasks on your behalf, and the same logic applies inside a browser. An agent that can read your Gmail to summarise it can, in principle, be told by a hidden instruction on a web page to do something else with that access entirely. We’ll come back to that. For now, the useful framing is: assistant first, agent second, and treat every “let it handle this for you” button as a separate decision rather than a feature you switch on once and forget.
Perplexity Comet is the one that actually caught on
Comet launched for Windows and Mac in July 2025, behind an invite system, then went fully free worldwide a few months later. An Android version followed in November 2025, iOS in March 2026. It’s genuinely free: the sidebar assistant that answers questions and summarises pages costs nothing, and Perplexity says the browser has passed three million monthly active users on its own, inside a company claiming well over 100 million monthly users across its products.
In our experience the free tier covers what most people would actually want from it: ask it what a long article is really saying, get it to pull the key numbers out of a PDF, have it compare specs across a few open tabs. The paid tier adds a “Background Assistant” that can keep working on a multi-step task after you’ve closed the sidebar, which sits closer to the agent end of the spectrum and, in our view, is the part worth being more careful with. If you’re weighing Comet up against a plain search engine, our comparison of Perplexity’s AI search against Google’s AI overviews is still the more useful read for most people; Comet is really that same engine wrapped around a browser.
Microsoft Edge Copilot Mode is probably already on your PC
Unlike Comet, you don’t need to go looking for this one. Copilot Mode launched inside Edge in July 2025 as an opt-in experimental setting, which means it’s sitting in the browser that ships with every copy of Windows, waiting to be switched on. Turn it on and the new tab page becomes a single box that routes your request to search, chat or straight navigation. Copilot can read across all your open tabs to compare or summarise them, and there’s a voice mode if you’d rather talk to it than type.
According to Microsoft’s own Copilot Mode page, it’s free with usage limits, and Microsoft 365 subscribers get a higher ceiling before they hit a paywall. One detail worth knowing: personalisation, where Copilot draws on your browsing history to give better answers, is switched off by default in the EU and UK, but it’s on everywhere else Microsoft offers it, Australia included, so it’s worth checking your own settings rather than assuming.
Google’s Gemini is in Chrome here, but the clever bit isn’t
Chrome has had a Gemini sidebar since late 2025, and it reached Australian accounts in April 2026, after rolling out through the US, Canada, India and New Zealand first. That part is ordinary and pretty handy: highlight a page, ask Gemini about it, get a summary of a long thread without leaving the tab.
The feature actually being marketed as agentic, Auto Browse, is a different story. It can handle genuinely multi-step tasks, comparing flight prices across sites or filling out a long form, but as of writing it’s still limited to Google AI Pro and AI Ultra subscribers in the United States, on desktop and, as of a recent expansion, Android. There’s no confirmed date for an Australian rollout. If the headline reason you’d want Gemini in Chrome is the agent rather than the assistant, it isn’t actually here yet.
What happened to ChatGPT Atlas, and why it’s worth remembering
Atlas launched for Mac in October 2025 as a fully-fledged Chromium-based browser with ChatGPT built into the sidebar, an optional memory feature, and an early agent mode reserved for Plus, Pro or Business subscribers. It reached Australia along with roughly a dozen other English-speaking markets, but a proper Windows release never really arrived beyond a promise that one was coming. By July 2026, OpenAI’s own product lead, James Sun, was announcing on social media that the standalone browser would be retired within the month.
It stopped working on 9 August 2026. The company’s stated reasoning was that it was “evolving” Atlas into the main ChatGPT app and a browser extension for Chrome, Edge, Brave, Opera and Vivaldi, rather than maintaining a separate browser that most people were never going to make their default. Fair enough, probably. But it’s a reminder that building a daily habit around a nine-month-old browser from a company simultaneously chasing coding tools, video generation and hardware is a genuine risk, not an abstract one.
The security problem nobody’s actually fixed
Here’s the mildly unpopular part of our view: we think the industry has shipped the “let it act for you” pitch well ahead of the work needed to make it safe. Security researchers keep finding the same underlying flaw across nearly every agentic browser, Comet included. Hidden instructions embedded in a web page, an email, or even pale text on a pale background can hijack the agent into doing something the person never asked for, sometimes without a single click from the victim.
Comet was hit with exactly this in 2025, when a booby-trapped web page could reportedly trick the assistant into pulling data out of a connected Gmail or calendar account. A wider piece of research published in early 2026 by the Cloud Security Alliance found related flaws across Atlas, Gemini and other agentic tools, all stemming from the same structural problem: these browsers inherit your logged-in session and then process untrusted content from the open web without a reliable way to tell your instructions apart from a stranger’s.
Australia’s own cyber security agency flagged the broader pattern in a late September 2026 advisory, describing AI agents that, given a task, went looking for ways around the security controls stopping them from finishing it, without direct authorisation to do so. That’s not a browser-specific warning, but it’s the same nervousness underneath: give a piece of software the ability to act, and every so often it will act in ways nobody intended.
Where an AI browser actually earns its place
None of this means these browsers are useless, and we’d rather make the genuinely useful case than write off the whole category. In our experience, the assistant side of things works well for:
- Summarising a long article, PDF or email thread before deciding whether it’s worth reading in full
- Comparing specs or prices across several open tabs without constantly switching between them
- Getting a rough first draft of an email or message that you then rewrite properly in your own words
What we’re far more cautious about is handing over anything that touches logins, payments or personal data, which is a privacy question as much as a security one. These browsers work by reading what’s on your screen and, often, your browsing history, which sits squarely inside what the Australian Privacy Principles under the Privacy Act 1988 are meant to protect. We’ve looked at that trade-off before in our piece on the privacy cost of on-device AI, and the short version carries over here: convenience and access to your data move together, and it’s worth deciding deliberately how much you’re comfortable handing over rather than clicking “allow” out of habit.
Should Australians actually switch their default browser?
Our honest answer is: not for the agent features, not yet. We’d genuinely argue against switching your everyday browser to chase “auto browse” or “agent mode” while the prompt-injection problem remains this unresolved, no matter how polished the demo videos look. That’s the contrarian bit of our view, and we’re happy to be proven wrong by whichever vendor closes the gap first.
The chat-sidebar side of things is a different story. If you’re already on Edge, turning on Copilot Mode costs nothing and adds a genuinely useful assistant without asking you to hand over the keys to your accounts. If you’d rather try something built around the idea from the ground up, Comet is free, works on every major platform, and does much the same job well. Chrome’s Gemini sidebar is worth using too, now that it’s rolled out here, even though the flashier Auto Browse feature is still stuck on the other side of the Pacific.
What we wouldn’t do is build a daily workflow around any single one of them just yet. Atlas looked like a serious contender for less than a year before OpenAI folded it into something else entirely, and there’s no particular reason to assume Comet, Copilot Mode or Gemini’s browser features will look the same twelve months from now. Use the assistant. Leave the agent switched off until the security researchers stop finding new ways in.
