YouTube Thumbnail Size Checker
Drop in your thumbnail. We check the size, shape, file size and type, and show it in the home feed, the Up next list and on a phone.
Four steps, under a minute
- 1Drop your image
Or paste it with Ctrl+V.
- 2Read the checks
Size, ratio, file size and type.
- 3Look small
Can you still read it in the Up next list?
- 4Fix in one tap
Download a 3840 × 2160 JPG under 2 MB.
3840 × 2160, up to 50 MB
YouTube recommends 3840 × 2160 pixels at a 16:9 ratio, with a minimum width of 640. Files can be JPG, GIF or PNG, up to 50 MB when you upload on desktop and up to 2 MB in the mobile app.
Most people see your thumbnail small, so big shapes and a few large words work better than detail. The timestamp sits in the bottom-right corner.
The checklist
- Size
- 3840 × 2160 (at least 640 wide)
- Ratio
- 16:9
- File
- JPG, GIF or PNG, up to 50 MB (2 MB on mobile)
- Keep clear
- Bottom-right corner (timestamp)
Common questions
Tap a question and we'll answer it in the chat. You can also type your own.
3840 × 2160 pixels, 16:9, at least 640 pixels wide. Up to 50 MB on desktop, or 2 MB if you upload from the mobile app.
Custom thumbnails need a verified account. Verify your phone number in YouTube Studio settings.
Use Download 3840 × 2160 JPG. We lower the quality step by step until it is under 2 MB, so it works on desktop and mobile.
No. It is opened and edited in your browser. Nothing is sent to us or anyone else.
Pairs well with
Title ideas that fit your topic and audience.
Crop and resize an image for any platform.
A structured description you can edit and post.
Every profile, cover, post and Story size.
Last reviewed 13 November 2026 · How we build our tools
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