What is Riff?
Riff is a free Chrome extension that helps you write replies on X, LinkedIn, Facebook and Instagram. You paste a rough point, and Gemini Nano — the AI built into Chrome — writes a fresh reply tailored to that exact post. You read it, edit it if you want, and press send yourself. Riff also answers DMs and drafts your own posts. Everything runs on your computer, with no account, no API key and no monthly bill. Riff never posts or sends anything for you.
Who it's for
- Social sellers and founders who want to reply to posts with a clear point instead of staring at an empty box.
- Creators building a presence on LinkedIn, X, Facebook or Instagram who post regularly and want a faster first draft.
- Anyone handling DMs at volume who wants a starting point for answers without handing over the send button.
Key features
Replies written for the exact post
Click the wave button next to a post's Reply or Comment button, and Riff reads the post and its context. Paste your rough point and it writes something fresh rather than copying your words back.
Dials for tone and pitch
Before generating, you choose how smart, how salesy and how adventurous the reply should be. The reply streams in sized to the site's character limit.
One-click rework
After the draft appears, you can reshape it with options like Shorter, Punchier, Softer pitch, Bolder, More human or + Question. Riff then fills the reply box and leaves sending to you.
DM answers and post drafts
In a chat you can leave your point empty and Riff answers what the other person wrote. Click into a new post box and the panel switches to drafting your own post, which you can then refine in plain words like a chat.
What stands out
Riff gives you a sharp first draft and keeps the send button in your hands.
That division of labour is the whole idea: the AI handles the blank-page problem, and you stay the one who reads, edits and decides. Because it runs on Gemini Nano inside Chrome, there's no account to create and no key to manage. The side panel follows whichever site, chat or post box you're on, opened from the toolbar or with Alt+Shift+R.
Worth checking out if…
You write a lot of replies and DMs across social platforms and want a faster starting point without paying a subscription or wiring up an API. It suits people who'd rather edit a draft than compose from scratch — and who insist on pressing send themselves. If you're on Chrome and want AI help that stays on your machine, Riff is a low-friction way to try it.
