See your thumbnail at the sizes people actually see it. Mobile feed, sidebar, search.
- 1
Drop in your thumbnail, ideally 1280 by 720.
- 2
Look at the smallest preview first. If the text is not readable there, it is not readable.
- 3
Toggle light and dark surroundings, because contrast changes which one wins.
- 4
Iterate until the smallest size still communicates one idea.
- Preview sizes
- 4 placements
- Recommended source
- 1280 x 720, 16:9, under 2MB
- Account
- Not required
What is youtube thumbnail preview tester?
A thumbnail preview tester shows a YouTube thumbnail at the small sizes it is really viewed at, rather than the full-size version you designed it at. APImage's tester renders your image at mobile feed, sidebar suggestion and search result scale side by side in the browser, which is how you find out that the text is unreadable before the video goes live.
What size is a YouTube thumbnail?
1280 by 720 pixels, 16:9, with a 2MB file size limit and JPG, PNG, GIF or WEBP accepted. That is the upload spec. The display sizes are far smaller, which is the whole reason to test at scale before publishing.
How big should the text be?
Three or four words at most, and large enough to read in the smallest preview here. A useful check: if the text height is less than about a tenth of the thumbnail height, it will disappear on a phone.
Why does my thumbnail look different on mobile?
Because the mobile feed shows it larger relative to the screen but with less contrast against surrounding content, and it may sit under a duration badge in the bottom right. Keep that corner clear and check both light and dark surroundings.
