Video chapter builder

About this tool

YouTube chapters fail in predictable ways: timestamps that do not match the video, chapters out of order, no 00:00 opener. Chatbots invent all three because they never saw your file. This builder works from your actual subtitle file — chapter starts snap to real cue times from the SRT or VTT you upload.

The model only names and summarizes chapters from the real transcript blocks. Sorting, monotonic increase and the guaranteed 00:00 first chapter are validated locally against YouTube’s rules before anything is shown, so the block you paste into your description works the first time. You also get a per-chapter summary table and show-notes Markdown for the podcast post.

How to use Video chapter builder

1. Add your provider API key in the key panel.
2. Upload an SRT/VTT subtitle file (or a plain transcript for untimed chapters).
3. Chapters are named from the actual transcript blocks and every timestamp is validated locally against YouTube rules.
4. Copy the chapter block straight into your YouTube description and export the show notes.

Keep the original files and inspect the exported result before publishing or sharing it.

Frequently asked questions

Why do the timestamps always work?

They come from your subtitle file, not from the model: chapter starts snap to real cue times, are sorted and checked locally, and a 00:00 first chapter is guaranteed — the three things YouTube requires and chatbots routinely get wrong.

What if I only have a transcript without timestamps?

You still get the chapter list with summaries as show notes, but no timestamp block — YouTube chapters need real times, and this tool will not invent them.

What else is exported?

A per-chapter summary table and a show-notes Markdown file with the chapter list and summaries, ready for a podcast description or blog post.

Where does my transcript go?

Only to the AI provider behind your own key, directly from your browser.

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