Free tool·Rules as of 30 October 2026
YouTube chapters not showing? Check your timestamps
YouTube turns timestamps into chapters only when three rules hold: the first timestamp is 0:00, there are at least three in ascending order, and each chapter lasts at least 10 seconds. Paste your description to find the line that breaks them and get a fixed list. No timestamps yet? Generate them from your subtitles with AI.
Your description is checked in the browser and never sent
YouTube chapter rules
| Rule | YouTube requirement | What the checker does |
|---|---|---|
| First timestamp | 0:00, the start of the video | moves it to 0:00 or adds “0:00 Intro” |
| Number of timestamps | at least three | shows how many are missing |
| Order | ascending, no repeats | sorts them and removes repeats |
| Chapter length | at least 10 seconds | merges a short chapter into the previous one |
| Line format | time at the start of the line: 0:00, 4:05, 1:02:30 | flags times mid-line and invalid times like 2:75 |
| Description length | up to 5,000 characters | counts characters |
Source: YouTube Help, Video chapters. Checked 30 October 2026. The 5,000-character limit is the counter of the Description field in Studio.
Why YouTube chapters are not showing
Start with the description format. Chapters disappear entirely, even if only one line is wrong:
- the first timestamp is not 0:00, for example 0:05 or 1:00;
- there are only two timestamps;
- timestamps are out of order or one repeats;
- two timestamps are less than 10 seconds apart;
- a time has a typo: 2:75 instead of 2:45, or 1.30 instead of 1:30.
If the format is right, the cause is outside the description. According to YouTube Help, chapters may be unavailable when:
- advanced features are off for the channel; check Studio → Settings → Channel → Feature eligibility;
- the channel has an active Community Guidelines strike;
- the video may be inappropriate for some viewers.
And the simplest one: the description was not saved. Press Save in Studio and refresh the watch page.
How to add chapters to a YouTube video
- Open Studio → Content and click the pencil next to the video.
- In the Description field, paste the list: one chapter per line, time first, then the title. The first line is 0:00.
- Press Save. Chapters appear on the video progress bar and in the description below it.
You do not have to count times by hand: the AI on this page makes chapters from your subtitles, and the checker shows right away whether they pass the rules.
Chapters from subtitles with AI
Paste the video subtitles: an .srt, .vtt or .sbv file from Studio, auto-generated ones work too, or the transcript from the watch page. The page packs the text into timed blocks and sends them to the DeepSeek model through the Monvilo server. The AI looks for topic changes and suggests chapters with short titles, using times only from your subtitles.
The AI answer goes through the same check as your description: 0:00 first, chapters of 10 seconds or more, all in ascending order. The list lands in the description field without touching the rest of your text, and Undo puts everything back.
The subtitle text is used for one answer and is not stored: the server records only the number of requests and their cost. The limit is 10 requests an hour and 30 a day per address.
Chapters and mid-roll ads
A chapter boundary is where the topic changes, which often makes it a good spot for a mid-roll: the ad starts between two thoughts rather than mid-sentence. Monvilo finds such pauses in the audio and subtitles and places ad breaks in Studio for you, then checks how YouTube reads them after saving.
FAQ
Why are my YouTube chapters not showing?
Usually because of the format: the first timestamp is not 0:00, there are fewer than three timestamps, they are out of order, or one chapter is shorter than 10 seconds. If the format is right, the cause can be outside the description: advanced features are off, the channel has a strike, or YouTube found the video may be inappropriate for some viewers.
Do YouTube timestamps have to start at 00:00?
Yes. The first timestamp marks the start of the video: 0:00 or 00:00, both work. If the first one is, say, 0:15, YouTube shows no chapters at all.
How many timestamps do I need, and how long must chapters be?
At least three timestamps, and every chapter at least 10 seconds long. So the video needs to be at least 30 seconds.
How do I write timestamps for a video over an hour?
With hours: 1:02:30. Timestamps under an hour can stay as 0:00 and 12:40 or be written as 0:00:00; the checker reads both.
What is the difference between my timestamps and automatic chapters?
YouTube can split a video into chapters on its own (automatic chapters in Studio). If your description has its own timestamps, YouTube shows yours instead of the automatic ones.
Do you store my description or subtitles?
The description is checked in your browser and never leaves it. Subtitles and chapter titles go to the Monvilo server and the DeepSeek model only when you press an AI button, for one answer, and the text is not stored. The server counts only the number of requests and their cost.
How good are the AI chapter titles?
The AI finds where the topic changes and suggests short titles. You know the video better, so read them and fix anything off. The AI takes times only from your subtitles, and the page code checks the YouTube rules.