notebooklm·video

For NotebookLM sources

Make any video fit under 200 MB.

NotebookLM turns away files over 200 MB. Drop a video here and get it back shrunk to one file, or cut into parts that each fit. It all happens in this tab: nothing is uploaded.

How it works

  1. Measure. The file is read in place, never copied into memory whole. Every frame's exact size and position is indexed, so the number of parts is known before anything starts.
  2. Pick a way to fit. Cut keeps the original picture and splits at key frames: seconds, lossless. Shrink re-encodes to H.264 at the sharpest resolution the 200 MB budget allows. Audio only keeps what NotebookLM actually transcribes.
  3. Encode on your device. WebCodecs drives your GPU's hardware encoder. If a part still comes out over the limit, it is encoded again, smaller. Every file you get is under 200 MB.
  4. Add to NotebookLM. Upload each part as a source in the same notebook. Parts are numbered, so they sort in order.

FAQ

What is the NotebookLM file size limit?

200 MB per source file. Anything larger is rejected at upload, so a long recording has to be compressed, cut into parts, or reduced to audio first.

Is my video uploaded anywhere?

No. Reading, cutting and encoding all happen inside this browser tab. There is no backend that could receive it. Once the page has loaded you can go offline and it still works.

Split or shrink?

Splitting is lossless and nearly instant, but you add several sources. Shrinking gives one source and takes a few minutes. For lectures, meetings and podcasts where only the speech matters, audio only is the smallest and fastest.

Why did I get fewer or more parts than size ÷ 200?

Cuts can only land on key frames, and every part carries its own index. The tool plans the cuts from the real size of every frame, then balances the parts so none of them is a tiny leftover.

Which browsers work?

Chrome and Edge are fastest (hardware encoding). Safari 17+ and Firefox 130+ work too. Lossless cutting works almost anywhere; shrinking needs WebCodecs video encoding.

Which formats can I drop?

MP4, MOV (including iPhone HEVC), MKV, WebM and MPEG-TS. The output is always MP4 (H.264 + AAC) or M4A for audio, which NotebookLM accepts.