3840 × 2160 pixels (16:9) is the size YouTube recommends for a video's custom thumbnail, and 2160 × 3840 (9:16) for a Short's. A video's thumbnail must be at least 640 pixels wide, a Short's at least 640 pixels tall. Upload a JPG or PNG under 2 MB from the YouTube app on a phone, or under 50 MB from YouTube Studio on a computer.
Checked on November 2, 2026, against YouTube's own help pages, linked inline and under Sources. To see your own thumbnail in YouTube's cards, use the free YouTube thumbnail preview.
The numbers
YouTube's custom thumbnail help gives these:
| Video | Short | Podcast playlist | |
|---|---|---|---|
| Recommended size | 3840 × 2160 pixels | 2160 × 3840 pixels | |
| Minimum | 640 pixels wide | 640 pixels tall | |
| Shape | 16:9 | 9:16 | 1:1 |
| File type | JPG or PNG | JPG or PNG | JPG or PNG |
| File size from a phone | 2 MB | 10 MB | |
| File size from a computer | 50 MB | 50 MB | 50 MB |
YouTube's page says the image "should be as large as possible", because it is also the preview image in the embedded player. A smaller 16:9 image, such as 1280 × 720 or 1920 × 1080, still meets the 640-pixel minimum.
The 2 MB limit applies only to uploads from a phone. If a thumbnail is over 2 MB, upload it from YouTube Studio on a computer, where the limit is 50 MB, or save it smaller. The YouTube Data API that scheduling tools use also takes up to 50 MB, and only JPG or PNG.
Who can add one
YouTube lets a channel upload its own thumbnail only once the account is verified. Without that, you pick one of the stills YouTube suggests. A Short's custom thumbnail can be added only in YouTube Studio on a computer, not in the app. YouTube also limits how many custom thumbnails a channel can upload each day, by country and channel history, and every thumbnail must follow the Community Guidelines.
To add one on a computer, open YouTube Studio, choose Content, open the video (or the Shorts tab, then the Short), and under Thumbnail choose Upload file, then Save. A new thumbnail can take a while to appear.
How it shows on a phone, a computer and a TV
YouTube draws one thumbnail at many sizes. Flaghand measured its cards on youtube.com and m.youtube.com:
| Where | Picture size | Shape |
|---|---|---|
| Home, on a computer (three to a row at 1440 pixels) | 347 × 195 | 16:9 |
| Search results, on a computer | 500 × 281 | 16:9 |
| Up next, on a computer | 248 × 139 | 16:9 |
| Shorts shelf, on a computer | 218 × 326 | 2:3 |
| Home, search and Up next, on a phone | 390 × 219, the full width | 16:9 |
| Shorts shelf, on a phone | 175 × 263, two to a row | 2:3 |
So the same picture shows anywhere from 139 to 281 pixels tall. Words that read at the largest size can blur at the smallest. The preview draws your image in each of these cards, light and dark.
On a phone, a vertical video with a 16:9 custom thumbnail gets an automatic 4:5 thumbnail on the home, Explore and subscription pages instead, YouTube's help says. Your 16:9 thumbnail still shows in the watch feed, watch history and off phones.
On a computer and a TV, YouTube's help counts these as non-mobile platforms, where the custom thumbnail always shows. YouTube publishes no separate TV size. 3840 × 2160 is the full resolution of a 4K TV screen, so a thumbnail made at YouTube's recommended size has the pixels a TV can show.
Safe areas
YouTube's help publishes no safe area for thumbnails. What covers part of the picture is the video's length, in the bottom right corner of every video card: 20 pixels tall, 8 pixels in from the edges on home and in search, and 4 pixels in Up next, as Flaghand measured them. On the Up next card, the smallest, a length such as 10:07 covers about the bottom right 660 × 370 pixels of a 3840 × 2160 thumbnail; a video over an hour has a wider one. Keep faces and words out of that corner.
The Shorts shelf shows a Short's 9:16 thumbnail at 2:3. Cut from the middle, as the preview draws it, that takes about 300 pixels off the top and bottom of a 2160 × 3840 image, so keep a Short's title and faces out of its top and bottom eighths.
Where Flaghand fits
Flaghand drafts YouTube videos and Shorts with their thumbnail for its owner to approve. Before approval, it checks that the thumbnail is a JPG or PNG and that the channel is verified, since YouTube sets custom thumbnails only on a verified channel. YouTube isn't open to every Flaghand workspace yet: Google has to review it first. Start a free Flaghand trial. For a Short's video file, see YouTube Shorts dimensions.
Sources
Checked on November 2, 2026.