One source, five depths
The right length for a summary depends on why you are reading it. Deciding whether to watch a video needs one paragraph. Preparing for an exam on it needs a study guide. Most summarizers give you one length and leave you to cope.
SumAI asks first. When you create a summary you pick a style, and the summary is written to that depth.
The five styles compared
| Style | What you get | Pick it when |
|---|---|---|
| TL;DR | One paragraph, just the point | You want to know whether it is worth your time |
| Standard | The key ideas, in a few minutes | You want the substance without the full length |
| Detailed | Key ideas with supporting detail | The reasoning and evidence matter |
| Study Guide | Concepts, definitions and takeaways | You need to learn and remember it |
| Chapters | A summary of each section in turn | The video is long and you want to navigate it |
Choosing by goal
“Should I watch this?” Use TL;DR. If the paragraph is interesting, you can always make a deeper summary of the same video.
“I need to brief someone.” Use Standard. It gives you the key ideas in a form you can repeat in a meeting or a message.
“I need to understand the argument.” Use Detailed. Shorter styles keep the conclusions and drop the path to them. Detailed keeps more of the path.
“I have an exam on this.” Use Study Guide, then run the quiz and flashcards. Concepts and definitions are what tests ask for.
“It is three hours long.” Use Chapters. You get the outline first, then a summary of each part, and you can jump into the video at any key moment.
What a shorter summary leaves out
Compression is a trade. A TL;DR of a ninety-minute lecture cannot hold its examples, its caveats or its tone. That is fine when you know it is happening, and a problem when you mistake the paragraph for the lecture.
Two habits keep you honest. First, match the style to the stakes: the more you will rely on it, the deeper the style. Second, when a point matters, check it. In SumAI that means tapping a timestamp or asking Ask AI where in the source the point comes from.
Language is a separate choice
Style decides how deep the summary goes. Language decides what it is written in. You set them independently, so you can have a Study Guide in Spanish of a lecture given in English. See summaries in 60+ languages.
Try it
The interactive example at the top of this page shows one video summarized five ways. It is an illustration of the styles, written for this site, not output copied from the app.
Last updated November 12, 2026.