Free · no signup · nothing uploaded
Drop your thumbnail and see whether it passes YouTube's size, ratio, file-size and format rules, with the duration badge, corners and progress bar drawn on top so you know what gets covered.
Drag and drop works too. The file is read in your browser and never uploaded anywhere.
The rules the checker applies, from YouTube's own upload help page.
A dark pill in the bottom-right corner on every layout. The classic mistake is a logo or a number hidden behind it.
A red line along the bottom for anyone who has started the video, and rounded corners that clip whatever touches the edge.
In the feed the image is a third of its export size and on phones it is blurred by compression. Keep the subject big and the text inside the dashed margin.
Once it passes here, see how it competes: test it in a mock YouTube feed next to real videos.
1280 by 720 pixels, in 16:9, as a JPG, PNG, GIF or WebP under 2 MB. That is the size YouTube recommends and the one every layout is built around. Anything narrower than 640 pixels is rejected at upload.
The part of the image that YouTube's own interface never covers. The duration badge sits bottom-right, a red progress bar appears along the bottom once someone has started the video, and the feed rounds the corners. Text or a face in those spots is partly hidden. The overlay on this page marks them on your image and the PNG download gives you the same guides as a transparent template for your design tool.
The image is not 16:9. A 4:3 or square image gets bars on the sides; a very wide one gets bars top and bottom. Crop to 16:9 before exporting. The aspect-ratio check above tells you which way yours is off.
Export as JPG at quality 80 to 90 instead of PNG. A 1280×720 JPG is usually 150 to 400 KB and looks identical in the feed, which shows the image at a third of that size anyway. Keep PNG only for flat graphics with hard edges.
Yes, as long as the file is under 2 MB and the ratio is 16:9. YouTube downscales it. There is no visible gain over 1280×720, and the file-size limit is harder to meet, so 1280×720 is the practical choice.
No. The file is read by your browser and never leaves your computer. Pasting a link fetches the thumbnail YouTube already serves publicly.
YouTube only publishes the 1280×720 file for videos that had a custom thumbnail uploaded at that size. Videos with an auto-generated thumbnail only have the 480×360 version, with black bars, and that is what viewers see too.
YouTube thumbnail tester — see it in the feed, in search and on a phone next to real videos.
Community post image size — see how the feed crops a post image to a square.
QR code generator — a QR code for any link, generated in your browser, never expires.
Built by Elevate — a community for people building faceless YouTube channels.