Consumer AI browsers
BrowserOS neo vs ChatGPT Atlas
Atlas puts ChatGPT in a browser you use, with agent mode on paid plans. BrowserOS neo gives any agent you already use a browser of its own, open source and free.
ChatGPT Atlas is OpenAI’s browser, released in late 2025. It is Chromium-based, with ChatGPT in a sidebar that can read the page, answer, and rewrite text, plus an agent mode that carries out tasks on sites. It launched on macOS first, is closed source, and its agent mode is reserved for paid ChatGPT plans.
BrowserOS neo brings no model of its own. It gives the agent you already use, Claude Code, Cowork, Codex, Cursor, anything speaking MCP, a browser signed in as you, running locally, with tabs you can watch and sessions saved as video. It is free and open source under AGPL-3.0, on macOS and Windows.
The short version
Choose BrowserOS neo when
- You want a browser driven by whichever agent you already use, not tied to one vendor’s model.
- You want it open source and running on your own machine.
- You want the agent in a separate browser so it never touches the tabs you are using.
- You want it free, on macOS or Windows, bringing your own keys.
Choose ChatGPT Atlas when
- You live inside ChatGPT and want it built into your browser.
- You want OpenAI’s own agent mode acting on pages for you.
- You are happy on macOS and on a paid ChatGPT plan for the agent features.
Side by side
| Dimension | BrowserOS neo | ChatGPT Atlas |
|---|---|---|
| What it is | BrowserOS neoAn open-source browser your existing agent drives over MCP. | ChatGPT AtlasA Chromium-based browser with ChatGPT built in and an agent mode. |
| Who drives it | BrowserOS neoYour AI agent, whichever one you already use. | ChatGPT AtlasYou, with ChatGPT helping, or OpenAI’s agent mode. |
| Open source | BrowserOS neoYes. AGPL-3.0, source on GitHub. | ChatGPT AtlasNo. Closed source. |
| The model | BrowserOS neoBring your own keys. Any MCP-capable agent. | ChatGPT AtlasOpenAI’s models, through ChatGPT. |
| Agent mode | BrowserOS neoAny agent that speaks MCP drives it, no extra tier. | ChatGPT AtlasYes, but reserved for paid ChatGPT plans. |
| Runs locally | BrowserOS neoYes. Logins, screenshots and replays stay on your machine. | ChatGPT AtlasA local browser, but the intelligence is OpenAI’s cloud. |
| Watch and replay | BrowserOS neoLive tabs and a dashboard, every session saved as replayable video. | ChatGPT AtlasNot a documented feature. |
| Platforms | BrowserOS neomacOS, Windows. | ChatGPT AtlasmacOS first. Other platforms announced as coming. |
Atlas is the ChatGPT browser: best if OpenAI’s model and its agent mode are what you want, and you accept a closed product on a paid plan. neo is model-neutral and open source: it gives a browser to the agent you already run, whoever makes it.
If you want an open-source AI browser you drive yourself rather than one your agent drives, the closer match is BrowserOS, the human daily-driver browser with agents built in. neo is the open-source option for when the agent is at the wheel.
Open source, model-neutral, and free.
Atlas ties the browser to OpenAI’s model and puts its agent mode behind a paid plan, so the browser and the subscription travel together.
neo ties the browser to nothing. Any MCP agent drives it, you bring your own keys, and there is no separate tier for the agent to act.
It is open source and local, so you can read what it does and keep your logins and replays on your own machine. For an AI browser, that auditability is the differentiator.
Common questions
Is there an open-source alternative to ChatGPT Atlas?
Yes. BrowserOS and BrowserOS neo are open-source AI browsers under AGPL-3.0. BrowserOS is the one you drive yourself, closest to Atlas in use. BrowserOS neo is the one your AI agents drive. Both run locally, are free, and let you bring your own model.
What is ChatGPT Atlas?
OpenAI’s Chromium-based browser with ChatGPT built into a sidebar and an agent mode that can act on websites for you. It launched on macOS first, is closed source, and reserves agent mode for paid ChatGPT plans.
Is ChatGPT Atlas free?
The browser is free to use, but its agent mode, the part that acts on sites for you, is reserved for paid ChatGPT plans.
How is BrowserOS neo different from ChatGPT Atlas?
Atlas is tied to OpenAI’s model with agent mode behind a paid plan. neo is open source, free, model-neutral (bring your own keys), runs locally, and is driven by whichever agent you already use, with every session replayable.
Check it yourself
Every claim about ChatGPT Atlas here was read off these pages on 17 September 2026. If something has gone stale, tell us.
What we could not confirm
- Atlas platform availability and plan boundaries change. This page says macOS-first and agent mode on paid plans rather than quoting current tiers.
- We describe agent mode from public reporting rather than a fixed capability list, which OpenAI updates over time.
Other comparisons
- vs CometConsumer AI browsers
- vs DiaConsumer AI browsers
- vs PlaywrightTest and scripting frameworks
- vs PuppeteerTest and scripting frameworks
- vs SeleniumTest and scripting frameworks
- vs agent-browserAgent browser infrastructure
- vs Browser UseAgent browser infrastructure
- vs Browser HarnessAgent browser infrastructure
- vs BrowserbaseAgent browser infrastructure
- vs StagehandAgent browser infrastructure
- vs Playwright MCPAgent browser infrastructure
- vs Claude for ChromeAn agent inside the browser you have
- vs Codex in ChromeAn agent inside the browser you have
- vs Kimi Browser ExtensionAn agent inside the browser you have
Give your agent a browser it can sign into.
Free, open source, and it sits beside the browser you already use.