18:42
A week of slow mornings in a small mountain town
Free tool
YouTube thumbnail tester
Pick your thumbnail and type your title. See them on the home page, in search, beside a video and on a phone, in light and dark, among other videos. Your image stays on your device.
or drop it here
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12:04
Your title shows here
9:15
The ten-minute dinner I make every Tuesday
24:07
Fixing an old bike with only basic tools
14:58
What I wish I knew before my first marathon
21:30
Rearranging a tiny flat so it feels twice as big
Free, no sign-up. Your images stay on your device.
What makes a thumbnail readable at small sizes
Most people meet your thumbnail at the size of a large stamp, while scrolling, for a second or two. In the suggested column beside a video it's 168 pixels wide. Anything that needs reading up close is lost.
Use three words or fewer, in thick letters that fill a good part of the height. One face or one object, big and close, reads better than a group or a wide scene. Strong contrast between the subject and the background matters more than the colours you pick: a light subject on a dark background, or the other way round.
Keep the bottom-right corner clear. The video's length sits on top of it in every view, and on the smallest thumbnails it covers about a quarter of the width.
Let the picture and the title say different things. The title sits right under the thumbnail, so repeating it in the image wastes the space. The picture shows the moment; the title says what happens.
Check it in light and dark
Plenty of viewers use the dark theme. A thumbnail with a black or very dark edge can melt into a dark page, and a pale one can fade into a light page. Switch the preview between the two and look at the edges of your image.
The grey neighbours are on purpose: with nothing else to look at, you see your own picture's contrast honestly. On the real page it sits among other bright thumbnails, which makes a simple, bold image matter even more.
Testing two thumbnails
YouTube Studio can test up to 3 thumbnails, or titles, on real viewers. The winner is the one with the most watch time, not the most clicks, and a test takes from a few days up to 2 weeks. It runs from a computer only, and not on Shorts.
Upload every option at 1,280 × 720 or bigger. If any one of them is smaller, YouTube shows all of them at 854 × 480 for the test.
Use this page before a test to narrow things down. Put two candidates side by side, look at them in every view and both themes, and drop the one that turns to mush at small sizes. Then test options that are clearly different: YouTube says options that are too alike make a test run longer.
Where your thumbnail shows up
The sizes this preview draws, taken from the site at common screen sizes. YouTube adjusts its layout now and then, so treat them as close, not exact.
| View | Thumbnail width | Title | Watch for |
|---|---|---|---|
| Home grid | About 270 to 400 px, with the window | 16 px, up to 2 lines | Three or four videos per row compete for the same glance |
| Search | Up to about 360 px | 18 px, up to 2 lines | Sits beside the channel name and a line of description |
| Suggested column | 168 px | 14 px, up to 2 lines | The length badge covers about a quarter of the width |
| Phone feed | The full width of the screen | 14 px, up to 2 lines | A small screen, often held at arm's length |
Questions
Asked often
Last checked 2 October 2026
No. The image is opened on your device and shown from there. Nothing is sent to us or to YouTube, and it's gone when you close the page.
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