Google shut down Project Mariner on May 4, ending the 17-month experiment it launched in December 2024. The project's landing page now displays a single farewell notice: "Thank you for using Project Mariner. It was shut down on May 4th, 2026, and its technology voyaged to other Google products."
The shutdown was first spotted and reported by Wired's Maxwell Zeff, and it did not come as a complete surprise. In March, Wired had reported that Google was already reassigning staffers away from the Project Mariner team, a sign the project was losing internal support months before the official end.
What Project Mariner could do
What made Project Mariner very useful was that it could take action on your behalf, not just answer questions about things. It navigated Chrome, searched job listings, filled out forms, and booked travel on sites like Expedia by taking frequent screenshots of whatever was on your screen, recognizing buttons and text, and then clicking and typing for you. Google later upgraded it to run up to 10 tasks simultaneously, so users could send the agent on several jobs at once while they continued other work. For people who had access, it felt like having an assistant operating inside the browser.
The frustration is that Project Mariner was still limited to a small pool of Google AI Ultra subscribers in the US when it shut down, meaning many users who wanted it never got full access before it disappeared. Google says the technology is moving into Gemini Agent and AI Mode rather than being discarded entirely, but anyone who wants a dedicated browser agent they can use independently today needs to look elsewhere.
Ogbonda Chivumnovu
5 Project Mariner alternatives you can use
1. Perplexity Comet
Comet is the most-used AI browser agent on the internet right now, accounting for 48.12% of all agentic browsing traffic recorded in April 2026 according to a report by security firm Human Security. Built by Perplexity, Comet replaces the browser's URL bar with a prompt box, where you can type a website address, ask a question, or give it a task and it figures out what you mean. Give it a job like researching flight prices or comparing products across different retailer sites, and it opens tabs, reads through them, and compiles the results for you.
Comet became free for all users in October 2025, with optional paid tiers at $20 a month for Pro and $200 a month for Max. For former Mariner users whose main use was research, comparison shopping, and pulling together information from multiple websites, Comet is the most direct replacement available today.
2. ChatGPT Atlas
This browser from OpenAI held 21.33% of agentic traffic in April 2026, making it the second-biggest player in this space. Atlas is a full Chromium-based browser built around ChatGPT, with an Agent Mode that lets the AI take a virtual cursor and navigate websites, fill forms, and complete multi-step tasks on your behalf. When it works, the experience is close to what Project Mariner promised: you give it a task, and it handles the process from start to finish without you needing to click through every step.
The trade-off is cost and platform access. Agent Mode requires a ChatGPT Plus subscription at $20 a month or Pro at $200 a month, and Atlas is currently macOS-only, with Windows, iOS, and Android versions still in development. If you are already a paying ChatGPT subscriber and use a Mac, Atlas is the strongest single alternative to Project Mariner.
3. Claude for Chrome
Anthropic's Claude for Chrome held 17.33% of agentic browser traffic in April 2026, putting it third in active use despite being a beta product many people outside developer circles have not yet heard of. Unlike Atlas and Comet, which require you to switch to a new browser entirely, Claude for Chrome is an extension that lives in a side panel inside your existing Chrome setup. It sees what you see, can navigate to pages, click buttons, fill forms, and manage multiple tabs at once, all through natural conversation.
It is available in beta to all paid Claude subscribers and works on both Chrome and Microsoft Edge. Users on the Pro plan are currently limited to the Haiku 4.5 model, while Max, Team, and Enterprise plan users can select more powerful models for heavier tasks. For anyone who wants Project Mariner-style automation without abandoning their current browser or bookmarks, Claude for Chrome is the lowest-friction option on this list.
4. Microsoft Edge Copilot Mode
Edge Copilot Mode launched in October 2025 and is the only option here that costs nothing, works across Windows, macOS, and mobile, and requires no new subscription to use. It is built into Microsoft Edge and offers autonomous task completion through an AI sidebar that can complete multi-step workflows, fill forms, conduct research across multiple sites, and handle bookings.
It does not match the raw capability of Comet or Atlas at their premium tiers, but for users who simply want to replace the core things Project Mariner did, including form filling, web research, and comparing options across sites, without paying for a new tool or installing a new browser, Edge is the most underrated option here. Windows users in particular already have it installed and may not realise the AI features are ready to use.
5. Google Gemini Agent
This is where Project Mariner's technology actually went. Google absorbed Mariner's web automation capabilities into Gemini Agent, which can now browse the web live, manage your Gmail inbox, archive emails, help book reservations, research topics across multiple sites, and handle multi-step tasks through a plan-and-confirm flow where Gemini tells you what it is about to do before doing it. It connects to Gmail, Google Calendar, Google Drive, Google Maps, and other Google apps you already use.
The catch is availability: Gemini Agent currently requires a Google AI Ultra subscription and is only available in the US in English. If you are already in that group and live inside Google's ecosystem daily, Gemini Agent is the most natural transition from Project Mariner. For everyone else, it is worth watching ahead of Google I/O on May 19th, where further expansion is expected to be announced.
Louis Eriakha
