For most of the web’s history a browser was a window: it fetched a page and displayed it. A new category of products is changing that definition. AI browsers embed a language model that can read the pages a user has open, answer questions about them, compare tabs, draft text and, increasingly, carry out tasks such as filling forms or managing an inbox. The field widened considerably in 2025, and on October 2 Perplexity made its Comet browser free to everyone worldwide. The following is a survey of seven products in this space.
Microsoft Edge with Copilot Mode
Microsoft has built its Copilot assistant into Edge as an optional mode that combines search, chat and navigation in a single input box. According to Microsoft, Copilot Mode can summarize web pages, answer questions about the content on screen and compare information across open tabs, and it connects with other Microsoft products such as Word and Excel. Its advantage is distribution: Edge ships with Windows, so the assistant is already on hundreds of millions of machines.
Opera with Aria
Opera’s Aria assistant is available on both desktop and mobile versions of the browser. It can generate and rewrite text, answer questions about the current page, work in multiple languages and respond to commands that span tabs. Opera positions Aria as a built-in helper rather than a full agent, which makes it one of the more conservative implementations on this list.
Dia
Dia, from The Browser Company, the maker of Arc, is organized around the idea of chatting with your tabs. Users can ask questions that draw on the content of every open tab at once, request summaries of complex pages and have the assistant carry context from one page to another. The result is a browser that feels closer to a research assistant than a traditional window onto the web.
Fellou
Fellou describes itself as an agentic browser. Beyond deep research across multiple sites, it is designed to execute multistep tasks autonomously, and it includes what the company calls agentic memory, which learns from a user’s activity to anticipate needs. Independent reviewers in 2025 generally placed it among the more capable, if less polished, agent-first browsers.
Sigma
Sigma is a free, privacy-focused AI browser that is still in a beta stage. It bundles a built-in AI agent, the option to run models locally on the device and an ad blocker, and the company says its agent can handle bookings, inbox management and routine workflows. As with any beta product, feature claims should be treated as goals rather than finished capabilities.
Genspark AI Browser
Genspark’s browser pairs on-device AI, which the company says can answer without an internet connection for core tasks, with agent tools that assist during browsing: comparing products, analyzing reviews and finding better prices. It also offers an autopilot mode and a store for Model Context Protocol tools, which lets the agent connect to external services. Genspark markets it as fast and free.
Comet by Perplexity
Comet is the product that has drawn the most attention. Built on Chromium, so it supports Chrome extensions and familiar settings, it integrates Perplexity’s answer engine directly into the browsing experience. The assistant can summarize a page, highlight key points, answer questions about content and perform tasks across sites on the user’s behalf. Perplexity first released Comet to a limited group on July 9, 2025, initially tied to its $200-a-month Max plan, and opened it to all users at no charge on October 2. The company has also announced free Pro access programs for students in several markets.
What to weigh
All seven browsers trade some privacy for convenience: an assistant that reads your tabs is, by definition, processing what you read. Security researchers have also flagged prompt injection, in which hidden text on a web page manipulates the browser’s agent, as a risk specific to this category. Users who want the benefits should check each product’s data policies, keep agent features scoped to tasks they understand, and remember that several of these products remain early-stage software.
