YouTube thumbnail size: the 16:9 rule and the file limits

What changed and what did not

The shape is the constant. A video thumbnail is 16:9 because it sits in the same frame as the player and the home feed cards, and YouTube Help asks for that ratio. What changed is the resolution ceiling. YouTube now recommends 3840 by 2160, the 4K frame, and accepts up to 50 MB when uploading from a computer, while a phone upload is still held to 2 MB. A 1280 by 720 thumbnail remains valid because it is well above the 640 pixel minimum width, and it is a sensible size when the file has to be uploaded from a phone.

The corner that is not yours

YouTube draws the running time in the lower right corner of every thumbnail, and on the home feed it can add a progress bar along the bottom once someone has started watching. Neither is published as a pixel box, but both cover the same area on every card. Keep faces, numbers and the main words out of the lower right quarter, and leave a margin along the bottom edge. On a phone, thumbnails are shown at a fraction of their width, so three or four large words survive where a sentence does not.

Shorts thumbnails are separate

A Short has its own 9:16 thumbnail, recommended at 2160 by 3840 with a minimum height of 640 pixels. YouTube Help says a custom Shorts thumbnail can currently only be added in YouTube Studio on a computer, and only on a verified account. The Shorts shelf also crops vertical covers in places, so the centre of the frame carries the subject. If no custom image is set, YouTube picks a frame from the video, which is a good reason to make the first second of a Short a clean, readable image.

Common mistakes

Uploading a 4:3 or square image leaves black bars or a crop on the player. Exporting a 4K thumbnail and then trying to upload it from a phone fails on the 2 MB mobile limit. Putting the title in small type duplicates the title YouTube already prints under the card. Using a busy frame grab with no single subject reads as noise at phone size. And an unverified account cannot upload a custom image at all, which is often mistaken for a size problem.

Thumbnails and this video builder

The video builder makes landscape videos at 1920 by 1080 and vertical videos at 1080 by 1920, and a 4K export, at 3840 by 2160 or 2160 by 3840, is a paid feature from the Starter plan. It does not make a separate thumbnail image, so the editor has no thumbnail canvas. A frame from the exported video can be saved with the video frame to image tool, then checked or scaled with the image resizer before uploading it to YouTube Studio. The blank 1280 by 720 PNG on this page is a 16:9 starting canvas for any image editor.

Questions people ask