Free YouTube tool
YouTube Thumbnail Resizer
Crop any image to the 3840 x 2160 YouTube recommends for a thumbnail, keep it under the 2 MB cap if you set it from your phone, and check it still reads at the small size it gets in search.
Last updated: 2026-08-03
A YouTube thumbnail is 16:9, at least 640 pixels wide, and a JPG or PNG. YouTube recommends 3840 x 2160, and the file can be up to 50 MB when you set it from a computer. The number that trips people up is the mobile app, which caps a video thumbnail at 2 MB: a tight budget for a busy thumbnail with a face, a background and large text, and the reason JPEG is the safer export.
The other thing worth internalizing is how small it gets. Search results show a thumbnail at a small fraction of the size you designed it at. Text that looks balanced at full size becomes unreadable, and a face that fills a quarter of the frame becomes a smudge. Crop tighter than feels comfortable.
This resizer takes whatever you have, a frame grab, a photo, an export from a design tool, and gives you the exact 3840 x 2160 frame with a focus point you control. Use the quality slider to land under 2 MB deliberately if you will set the thumbnail from your phone. It runs entirely in your browser and nothing is uploaded.
Your image never leaves your browser. The crop and the export both run on your device, and nothing is uploaded to us. HEIC photos straight from an iPhone only decode in Safari, so export a JPEG copy first if yours will not open.
YouTube sizes to export
Each one is cropped to fill the frame, centered on the focus point you pick.
Focus point
What every crop stays centered on when the shapes do not match.
Focus: Center
Export format
0.85 is the safe default. Push to 0.95 for images with text, drop toward 0.7 only when you are fighting a tight file size cap.
Re-encoding through canvas also drops the EXIF block, so the file you download carries no GPS coordinates, camera model or timestamp.
YouTube image sizes
Every YouTube surface that takes a still image, with the size to export at and the ceiling the file has to stay under.
| Surface | Export at | Aspect ratio | Max file size | File types |
|---|---|---|---|---|
| Thumbnail | 3840 x 2160 | 16:9 | 50 MB | JPG, PNG |
Sizes verified 2026-07-31. The file size ceilings are the ones the networks publish, and a scheduling tool sitting in front of them can be tighter still.
JPEG or PNG, and what the quality slider does
The resolution decides whether your image fits the frame. The format and the quality setting decide whether it fits the file size cap, and those are two different problems.
JPEG
Photographs, screenshots of video, anything with gradients
Lossy, and that is the point: a 1080 pixel wide photo lands between 100 KB and 500 KB at quality 0.85, which clears every file size cap on this page with room to spare. The artifacts it introduces hide well in detail and texture.
PNG
Logos, charts, diagrams, screenshots of text, flat color
Lossless, so text stays crisp and flat areas stay flat. The cost is size: the same image can be five to ten times larger than the JPEG, which is what pushes a thumbnail past 2 MB or a Facebook image past 4 MB.
The quality slider only applies to JPEG, and it runs from 0.6 to 1.0. At 0.85, the default here, the difference from the original is invisible at normal viewing size on almost any photograph. Above 0.95 the file grows quickly for very little gain. Below about 0.75 you start to see blocking in skies and other large flat areas, which is the first thing that gives away an over-compressed image.
One thing worth knowing either way: every network re-compresses what you upload. Exporting at maximum quality does not protect the detail, it just means the image is compressed twice. A clean file at the recommended size and a sensible quality survives that better than an enormous one.
YouTube image tips
- Export at 3840 x 2160, the size YouTube recommends. From a computer the file can be up to 50 MB, so resolution is rarely what gets a thumbnail refused.
- Use JPEG rather than PNG if you set thumbnails from the YouTube app. The app caps the file at 2 MB, a detailed PNG passes that easily, and the visible difference on a photographic thumbnail is close to nothing.
- Check the design at a small size before you commit. That is how search shows it, and it is the real test of whether your text and your subject survive.
- Three or four words maximum on the thumbnail, set very large. The video title sits right next to it, so the thumbnail does not need to repeat the title.
- Keep the bottom right corner clear. The duration badge is stamped over it in every surface YouTube renders.
- Crop faces larger than feels right on a big screen. A face that fills a third of the frame at full size is still small at thumbnail size.
Frequently asked questions
What size should a YouTube thumbnail be?
YouTube recommends 3840 x 2160 pixels at 16:9, with a minimum width of 640 pixels, as a JPG or PNG. The file can be up to 50 MB from a computer and 2 MB from the YouTube mobile app. YouTube displays the same image everywhere from a full width home page card down to a small preview in search.
Is my thumbnail uploaded to you when I resize it?
No. The image is decoded and redrawn with canvas inside your browser and the result is saved locally. Nothing is sent to our servers, and nothing reaches YouTube until you set the thumbnail in Studio yourself.
Why does my iPhone screenshot or photo fail to load?
If it is a HEIC file, most browsers cannot decode it and the tool has nothing to draw. Export a JPEG copy from Photos, or switch Settings, Camera, Formats to Most Compatible. YouTube does not accept HEIC thumbnails either, so the conversion is needed regardless.
Does resizing remove metadata from the image?
Yes. Re-encoding from a canvas produces a file with no EXIF block, so GPS coordinates, camera model and timestamps are all stripped. If your thumbnail is a photograph taken at home, that is one less thing published with the video.
Will the quality drop when I resize a thumbnail?
Barely, as long as the source is at least as large as the output. The JPEG encode is where quality is spent: 0.8 to 0.85 is a sensible range when you need to stay under the 2 MB mobile cap, and below about 0.7 you start to see blocking in flat backgrounds, which is very visible on a thumbnail with large areas of solid color.
Why does YouTube reject my thumbnail?
Check three things: the file has to be under 50 MB from a computer or 2 MB from the mobile app, at least 640 pixels wide, and a JPG or PNG. Custom thumbnails also need a verified YouTube account. A PNG over the 2 MB mobile cap is the most common miss, and re-exporting as JPEG is usually the fix.
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