Setup guide

Install LM Subs in about two minutes

LM Subs is not on the Chrome Web Store yet, so installation means loading it unpacked once. The steps below take about two minutes and you only do them a single time. Chrome keeps the extension loaded across restarts.

1. Download and unzip

Download lm-subs-v0.2.8.zip from the LM Subs home page, then extract it into a folder you keep, for example Documents. Chrome reads the extension from that folder, so do not delete it afterwards.

2. Load it in Chrome and pin it

1. Open chrome://extensions and turn on Developer mode in the top right.
2. Click Load unpacked and choose the extracted folder.
3. Open Chrome's puzzle menu and pin LM Subs so the icon stays in the toolbar.

3. Save one free speech-to-text key

Create a free key at console.groq.com/keys. No credit card is needed, and the free tier covers roughly eight hours of audio per day. Paste the gsk_... key into the LM Subs popup and click Save.

4. Play anything in NotebookLM

Open a notebook and play a Video Overview or an Audio Overview. Captions generate in a few seconds, the CC toggle appears in NotebookLM's own bottom play bar, and you can export SRT, VTT, TXT, MD, CSV or JSON from the caption menu.