YouTube Chapters Checker

Paste the timestamp list from your video description. This tool checks it against YouTube's chapter rules, marks every problem on the line where it happens, and gives you a fixed list to copy. It runs entirely in your browser: nothing you paste is sent anywhere.

The rules YouTube states

YouTube's help page on Video Chapters says that to add your own chapters you put a list of timestamps and titles in the video description, and:

• the first timestamp you list starts with 00:00;
• the video has at least three timestamps;
• the timestamps are in ascending order;
• the minimum length for a chapter is 10 seconds.

The same page notes a few things that can stop chapters showing even when your list is right: you may need access to Advanced features first, chapters aren't available if the channel has an active strike or the content may be inappropriate for some viewers, and adding your own chapters overrides automatic chapters.

What this checker adds on top

YouTube's page doesn't spell out a timestamp format. This tool accepts the forms creators normally use, M:SS, MM:SS and H:MM:SS (with or without brackets), and flags things that are almost always typos: seconds or minutes above 59, a missing title, or a duplicate timestamp. If you give it the video length, it also checks that the last chapter is at least 10 seconds long and that no timestamp runs past the end.

How the fix works: lines are sorted into ascending order, duplicates are dropped, any chapter shorter than 10 seconds is merged into the one before it, and if your list doesn't start at zero a 00:00 Intro line is added (you'll want to rename it). If you have fewer than three chapters after that, there's nothing safe to invent, so it tells you to add more.

Using the same list for podcasts

Other platforms have their own minimums. Spotify's help page says chapters need at least 3 per episode and at least 30 seconds between start times. Apple Podcasts reads chapters from the episode description too, asking for the first at 00:00:00 and at least three chapters, and recommends chapters no shorter than two minutes. The checker shows these as side notes, not errors. Full walkthrough: how to add chapters to your podcast.