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YouTube description generator

Describe your video and get three description drafts under YouTube's limit, with the hook first and your own chapter times, or fill in the template below.

Used as written when chapters are on: start at 0:00, at least 3, in time order. Without them you get a block to fill in; times are never made up.

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What a good YouTube description holds

  1. The hook: one or two sentences on what the viewer gets, in the first lines that show before 'more'.
  2. The details: what the video covers, with one or two main keywords used the way people search.
  3. Chapters: your own times and titles, the first at 0:00, so viewers can jump to the part they need.
  4. Links: your page, product or playlist, each on its own line.
  5. A call to action: one short line, such as subscribing or watching the next video.

YouTube description template

Description with chapters

[What the viewer gets from this video, in one or two sentences.] Chapters 0:00 [Intro] [mm:ss] [Chapter title] [mm:ss] [Chapter title] [Two or three sentences on what the video covers, using your main keyword once.] [Link label]: [link] Subscribe for more [topic] videos. #[hashtag] #[hashtag]

Short description

[What the viewer learns or gets, with your main keyword.] [One sentence on who the video is for.] More: [link]

Use this tool from code

The same tool is an API call with a free account's API token; each new generation spends 1 AI credit of your workspace, and a repeated request is free. It also works with our 9 SDKs and the MCP server.

curl 
curl -X POST https://postboost.co/app/api/tools/youtube-description-generator -H 'Authorization: Bearer YOUR_API_TOKEN' -H 'Content-Type: application/json' -d '{"text":"A beginner sourdough bread recipe: feeding the starter, mixing, shaping and baking in a Dutch oven.","keywords":"sourdough bread, beginner","chapters":true,"chapter_lines":["0:00 Intro","1:30 Feeding the starter","4:10 Shaping","9:45 Baking"],"cta":"subscribe"}'

API docs for this tool SDK quickstart

Last verified:

Sources:

Descriptions that viewers and search can read

A description has two jobs. The first lines tell a viewer why the video is worth their time, because that is what shows before they click for more. The rest helps search understand the video and gives viewers the chapters and links they came for. The generator writes three drafts that keep the hook first, use your keywords naturally and fit YouTube's limit, counted in bytes like the YouTube Data API.

If the AI part is switched off, the template on this page works the same way. Fill in the brackets with your own details, keep the chapter times your editor shows, and replace every [link] before you publish.

Tips for better YouTube descriptions

  • Lead with the result. Say what the viewer will be able to do or know, not that the video exists.
  • Use one or two main keywords. Describe the video the way your viewers would search for it, without a list of tags.
  • Add chapters for longer videos. Times from your own edit help viewers jump to the part they need.
  • Keep links real. Every link should go to a page you control and that matches the video.
  • Check before you paste. Make sure each sentence matches what the video actually shows.

From description to a published video

A description is part of the upload. In PostBoost you can write the title, the description and the posts that promote the video with AI, check the video specs, and schedule YouTube with your other networks on one calendar.

How to use

  1. Describe what the video covers in a few sentences, using the words people would search for.
  2. Add one or two keywords if you have them, and choose a call to action: subscribe, a link or none.
  3. For chapters, choose Add chapters and paste your own time and title lines, starting at 0:00.
  4. Generate three descriptions; each shows its size against YouTube's 5,000-byte limit.
  5. Pick one, replace every [link] with a real link, check the facts and paste it into YouTube Studio.

FAQ

How long can a YouTube description be?

YouTube Help gives 5,000 characters. The YouTube Data API counts 5,000 bytes, so letters such as é and most emoji take more than one. Every draft here fits the byte limit, which means it fits either way, and none uses the < and > characters YouTube does not allow.

What should the first lines of a description say?

What the viewer gets from the video. YouTube shows the first few lines before viewers click to see the rest, so the generator puts the hook there and keeps the keywords natural instead of listing them.

Does the generator write chapters for my video?

No. It cannot watch your video, so it never makes up times. Paste your own lines, such as 0:00 Intro and 1:30 Feeding the starter, and they are added exactly as written. YouTube needs the first chapter at 0:00, at least three chapters in time order and at least 10 seconds per chapter. Without lines you get a block to fill in.

Why does the description say [link]?

The AI does not know your links, so it marks where one belongs instead of inventing an address. Replace each [link] with your own page, product or playlist before you publish.

How does the AI description generator work?

When it is switched on, your summary and options are sent to PostBoost and our AI provider, which writes three different descriptions. The same request returns the cached result, and each visitor gets a few free generations per day, shared with the other AI tools.

Why is the generator form not shown?

The AI part can be switched off, for example when the monthly free allowance is used up. The description template still works, and a free PostBoost account lets you write posts with AI and publish to YouTube inside the app.

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