According to AlphaMoat, as of 2026-09, the Chrome extension SubChat has 108 users (+0% MoM) — ranked #4,102 of 9,324 AI browser extensions, and #1,002 of 2,418 in General AI.
Highlight text and ask focused follow-ups — plus Web Mind, your private on-device persona across every AI and website. Ever asked a follow-up mid-answer and watched the conversation wander off the thing you were actually working on? SubChat fixes that. Highlight any line, click Ask, and a small side-chat opens right there. Your main conversation stays exactly where it was.
It runs on the AI session you are already signed into. No API key to paste, no per-token charges, no account with us — because there is no server of ours in the middle. Your text goes from your browser straight to the AI you are already using.
HOW IT WORKS
tidied away automatically when you close the widget.
FREE, AND PRO
10 a day, seeded with your selection.
turns, whole chat, full page), saved searchable history, Keep & Continue in Claude, web mode on ChatGPT and non-AI websites, a configurable engine order, per-chat model selection, web search and file attachments, and Web Mind's advanced on-device persona, Context Vault and Workspaces.
WEB MIND — OPTIONAL, AND OFF BY DEFAULT
Web Mind is a private memory that makes every new chat start already knowing your context: how you like answers written, what you are working on, what is in the documents you added.
It is switched off when you install. Nothing is captured until you choose a learning mode, and you can pause it, block individual sites, review every memory, and delete everything in one click.
topic-level navigation graph. Browser navigation access is requested separately and removed when you switch the sensor off.
Everything is encrypted on your device with a key that never leaves it. Nothing is uploaded to us, because there is nowhere to upload it to.
Passwords, payment fields and government IDs are never learned. Incognito is excluded. A scrubber redacts secrets and high-entropy tokens before anything is stored.
CONTEXT VAULT
Add a résumé, a contract, a spec, or an exported chat history. SubChat indexes it locally and pulls the relevant passage into an answer, showing which source it came from. PDF, DOCX, TXT and Markdown are supported. Scanned image-only PDFs cannot be read, and SubChat tells you rather than failing quietly.
PRIVACY, PLAINLY
key if you chose to add one.
Full policy: https://subchat.sohamaggarwal.com/privacy
NOT AFFILIATED
SubChat is an independent project and is not affiliated with, endorsed by, or sponsored by Anthropic, OpenAI or Google. "Claude", "ChatGPT" and "Gemini" are trademarks of their respective owners, used here only to describe compatibility.
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+ CompareData month: 2026-09 · User counts and ratings come from public Chrome Web Store data, aggregated monthly. See methodology.