Fylun Extension
Every model, on every page.
A side panel that follows you around the web. Ask about the page you’re on, switch between GPT-5.6, Claude, Gemini, Grok and Kimi mid-thread, and pay from the same wallet as the web app.
- Chrome Web StoreIn review
- Firefox Add-onsIn review
- Safari ExtensionsIn review
INCLUDED IN EVERY PLAN · FREE TIER · ONE WALLET, EVERY SURFACE
The whole catalog, one keystroke away.
Every model, no tab-switching
The same catalog as the web app — GPT-5.6, Claude Opus 4.8 and Sonnet 5, Gemini 3.6, Grok 4.5, Kimi K3, DeepSeek — in a side panel over whatever you're reading. Switch models mid-conversation without losing the thread.
It can see the page
Ask about the article, the PR diff, the spec, the dashboard you're staring at. The extension reads the page you're on so you don't paste half of it into a chat box and lose the formatting.
One wallet across every surface
Extension usage draws from the same balance as the web app, mobile and Fylun Code. No second subscription, no per-seat surprise — you're paying for tokens, not for the window they're spent in.
Conversations follow you
Start a thread in the extension, finish it on the web. History, model choice and attachments are the same account, not a separate silo that forgets what you asked.
Reasoning control where it matters
Per-model thinking controls come through to the panel: effort levels on the OpenAI o-series and GPT-5.x, thinking budgets on Claude and Gemini. Spend more compute on the hard question, not on every question.
Built on Manifest V3
Modern extension platform, minimum permissions, no remote code. It asks for access to the page you invoke it on — not a blanket grant over everything you browse.
Common questions.
When does the extension launch?
It's built and in final testing ahead of store review. Chrome, Firefox and Safari listings go live together — leave your email above and you'll hear the day it ships, not a week of teasers beforehand.
Does it cost extra on top of Fylun?
No. The extension is included with every Fylun plan, including the free tier, and draws from the same wallet as the web app. There is no separate extension subscription.
Which browsers will be supported?
Chrome and Chromium-based browsers (Edge, Brave, Arc, Opera) at launch, plus Firefox and Safari. It's a Manifest V3 extension, so anything on a current Chromium build works.
What can it see on the page?
Only the page you invoke it on, and only when you invoke it. It doesn't run in the background across your browsing, and page content is sent to the model you picked for that message — the same routing and retention rules as the web app.
Do I need a Fylun account?
Yes — the extension signs in to your Fylun account so conversations, model access and your wallet balance are shared with the web app. The free tier is enough to use it.
How is this different from a single provider's extension?
A provider extension gives you that provider's models and a bill from that provider. Fylun gives you every major lab behind one login and one balance, so you can put a cheap model on a summary and a frontier model on the hard question in the same panel.