How to Write a YouTube Description
A good description does three jobs at once: helps search, helps suggested placement, and helps the viewer decide to watch.
The first two lines matter more than the rest combined
YouTube shows roughly the first 100-150 characters of a description in search results and above the fold on the watch page before a viewer has to click "more." Whatever you put there should describe what the video actually delivers, ideally including the same core keyword phrase used in the title — not a channel intro or a "hey guys welcome back" that could open every video you've ever made.
The description is read by two audiences, not one
A human skims it to decide whether to keep watching or to find a timestamp; YouTube's systems parse it for topical signals that inform search ranking and suggested-video placement. Writing only for the human (vague, casual, no keywords) or only for the algorithm (a keyword-stuffed list) under-serves the other reader. The best descriptions read naturally while still using the terms someone would actually search for.
Timestamps do double duty
Chaptered timestamps (`0:00 Intro`, `1:24 The mistake`, etc.) let viewers jump to the part they want, which is useful on its own — but they also give YouTube structured, topic-labeled text to index, effectively handing the algorithm a summary of the video section by section. A video without timestamps gives up this signal for free.
Don't front-load links and boilerplate
Putting a sponsor link, social handles, or a standard disclaimer block as the very first lines pushes the actual content description below the fold, where fewer people and less of the visible-in-search text will ever reach it. Put the substance first; move the standard boilerplate (socials, sponsor disclosure, affiliate disclaimer) below the fold.
Length should match what the description needs to do, not a fixed target
A tutorial video with steps, tools used, and timestamps legitimately needs more space than a short vlog update. Padding a thin description to hit an arbitrary word count reads as filler and dilutes the keyword signal you do have; a short, accurate description outperforms a long, vague one.
Pair the description with a title that's actually been checked
A strong description can't rescue a weak or misleading title — get the title right first. The Headline Analyzer on this site scores a title before you publish it, and the YouTube Description Generator writes a structured description (with timestamps and keyword placement handled) once the title's locked in.