YouTube Thumbnail Size: Pixels, Aspect Ratio and File Limits

Most guides still say a YouTube thumbnail should be 1280 x 720 pixels. That was YouTube’s own advice for years, but the help page has changed. The recommended YouTube thumbnail size is now 3840 x 2160, the 640 pixel minimum width stays, and the file size limit depends on whether you upload from a phone or a computer. Below are the current numbers, the Shorts version, and how to resize an image without stretching it.

Every number here comes from YouTube Help, checked on 2 November 2026. If anything disagrees with Add custom thumbnails, the help page wins.

Quick answer: YouTube recommends a thumbnail of 3840 x 2160 pixels (16:9), with a minimum width of 640 pixels. Upload a JPG or PNG. The limit is 2 MB when you upload from a phone and 50 MB from a computer. Shorts thumbnails are vertical, 2160 x 3840 (9:16). 1280 x 720 still works, because it is 16:9 and above the minimum.

YouTube thumbnail size in pixels

The firm rules are the 16:9 shape and the 640 pixel minimum width. Here are the common 16:9 sizes.

A 3840 x 2160 image has nine times the pixels of 1280 x 720. YouTube’s thumbnail and title tips say thumbnails show up differently across devices and ask you to make the image as large as possible. On a TV, the extra pixels are the difference between crisp text and blurry text.

Is 1280 x 720 wrong, then? No. It is 16:9 and twice the minimum width, and it looks fine on a phone. Make new templates at 3840 x 2160, though.

Aspect ratio: 16:9 for videos, 9:16 for Shorts

YouTube Help tells you to “try to upload a thumbnail with an aspect ratio of 16:9” for regular videos. Every size in the table above is 16:9: 3840 ÷ 2160, 1920 ÷ 1080 and 1280 ÷ 720 all come to 1.78.

The ratio matters more than the pixel count. Squash a 4:3 phone photo into 16:9 and faces look wide. Crop first, then resize.

For Shorts, the help page gives 2160 x 3840 pixels with a minimum height of 640 pixels, and 9:16 for uploaded files. Custom Shorts thumbnails are uploaded in YouTube Studio on a computer. In the YouTube app, the Shorts help page says you can choose a frame from your Short as the thumbnail instead.

File size limit and formats

The custom thumbnails page says the limit depends on the device you upload from. The 2 MB phone limit is the one that catches people. A detailed 3840 x 2160 JPG with lots of texture can go over it. A 1920 x 1080 export has a quarter of the pixels, so it is much easier to keep under the limit. Upload from a computer and it rarely matters.

For formats, YouTube asks for images such as JPG or PNG. JPG gives the smallest file for photos, faces and gradients. PNG keeps flat colour and small text sharp, but the file is bigger. Near the 2 MB limit, use JPG. The JPG vs PNG vs WebP vs AVIF guide explains the trade-off.

Who can upload a custom thumbnail

Not every account can. YouTube lets you pick one of the auto-generated thumbnails, or upload your own if your account is verified. Verification is a phone check: you enter a number and get a code by text or voice call. One phone number can be used for two channels a year. If the “Upload file” button is missing or greyed out, check verification first.

The thumbnails policy also bans nudity, sexual content, gore meant to shock, and thumbnails that mislead viewers about the video. A thumbnail that breaks it is removed and can lead to a strike.

How to resize an image to YouTube thumbnail size

ResizeAny runs in your browser, so the image never leaves your device.

1. Open the YouTube thumbnail preset (1280 x 720) or the 3840 x 2160 preset for YouTube’s current recommendation. For a middle size, use 1920 x 1080.
2. Check your image’s shape. If it isn’t already 16:9, choose Crop under Ratio & fit, which trims the edges evenly from the center. To pick which part stays, use the crop tool first. It doesn’t have a 16:9 button, so pick Freeform and watch the pixel readout in the crop window: 4000 x 2250 or 3000 x 1688 are both 16:9. Do neither and the image gets stretched, because the preset starts on Stretch.
3. Choose JPG as the output format.
4. If you’ll upload from a phone, type 1.9 in the target file size box and pick MB. ResizeAny counts a megabyte as 1,024 KB, so a little under 2 MB is safe whichever way YouTube counts. It lowers JPG quality until the file fits and keeps your pixel size.
5. Download and upload in YouTube Studio under Thumbnail.

For Shorts, use the 2160 x 3840 preset and the crop tool’s 9:16 option, which does exist. For a playlist’s worth of thumbnails, bulk resize takes up to 100 images at once.

ResizeAny won’t add text or graphics. Design the thumbnail in your editor, then use it to hit the size and file limit.

Where thumbnails appear, and the corner to keep clear

The same image shows in search, on the home page, in suggested videos and on TVs, at very different sizes. In suggested videos on a phone it is a few centimetres wide. So shrink your design to about 320 pixels wide on screen before you upload. Can’t read the text? Use fewer words or bigger letters.

YouTube’s tips page suggests the rule of thirds and warns that too much colour and detail can overwhelm the eye. It publishes no safe area for the video length label. On youtube.com and in the app, the video length is printed over the bottom-right corner of the thumbnail, so keep faces and key words out of that corner.

YouTube also lets you A/B test up to three thumbnails on one video. The winner is picked by watch time, not clicks, and a test can take up to two weeks. That settles “text or no text” better than any guide, this one included.

More sizes for other platforms are in the social media presets. For Instagram, see our Instagram image size guide.