YouTube thumbnail requirements
| Requirement | Video thumbnail | Shorts thumbnail |
|---|---|---|
| Recommended size | 3840×2160 | 2160×3840 |
| Minimum | 640 px wide | 640 px tall |
| Aspect ratio | 16:9 | 9:16 |
| Maximum file size | 2 MB from a phone, 50 MB from a computer | same |
| Formats | Image formats such as JPG or PNG | same |
Source: YouTube Help, add video thumbnails, retrieved 2026-10-14. Podcast playlists use 1:1 images instead.
Why the ratio matters most
YouTube asks for 16:9, the same shape as a regular video. An image of another shape does not fill a 16:9 frame, so it ends up cropped or with empty bars, and text near the edges can disappear. Start from a 16:9 canvas and keep the important part of the image inside the middle of the frame.
The corner you should keep clear
YouTube places the video length in the bottom-right corner of every thumbnail, and a red progress bar along the bottom edge once someone has watched part of the video. YouTube publishes no measurements for either, so the overlay in the checker is an illustration. The rule of thumb is simple: nothing important in the bottom-right corner or on the bottom edge.
Size versus sharpness
The minimum of 640 pixels wide keeps a thumbnail accepted, not sharp. Large screens and TVs show thumbnails much bigger than a phone does, and YouTube now recommends 3840×2160. Export at the largest 16:9 size you have and keep the file under 2 MB so it uploads from any device: JPG at high quality usually gets there, while a detailed PNG can be larger.