Compress YouTube thumbnails
The most common upload failure is not file size, it is the format. YouTube rejects WebP outright, so output here is locked to JPEG.
- Cap
- 2 MB (the new 50 MB is still rolling out)
- Formats
- JPG / PNG / GIF / BMP, never WebP
- Size
- 1280×720 at 16:9, 640 px minimum width
Target size 2 MB
Drop images or videos here
Or click to browse, or just hit Ctrl + V to paste a screenshot
Images: JPEG / PNG / WebP / GIF / BMP · Videos: MP4 / MOV / WebM / AVI
Results
Before / after
The trap nobody warns you about: format
Most people assume a failed thumbnail upload means the file is too big. More often it is the format. YouTube accepts JPG, PNG, GIF and BMP, and rejects WebP.
That became a practical problem in 2026, because almost every online compressor now defaults to WebP, it is around 30% smaller than JPEG at matched quality, which is the right call for nearly everything except this. You can compress ten beautiful thumbnails and have all ten rejected.
The format selector on this page is locked to JPEG. That is deliberate, not a bug.
Size and dimensions
| Property | Value | Notes |
|---|---|---|
| File size | 2 MB | The long-standing cap; always safe |
| New cap | 50 MB | Rolling out since March 2026, not universal |
| Recommended size | 1280×720 | 16:9, YouTube’s own guidance |
| Minimum width | 640 px | Accepted, but soft on large screens |
| Practical sweet spot | 200 KB – 1 MB | Below this, banding starts to show |
Even where the 50 MB cap has landed, a thumbnail has no use for it. What matters is being as small as possible while still looking sharp, since thumbnails load by the dozen on every listing page.
Why thumbnails look blurry
- The source was too small. A 640 px image stretched into a desktop-sized placement will look soft. Start at 1280×720.
- It was over-compressed. YouTube re-encodes your file to produce every placement size. If you already squeezed it to the limit, that second pass has nothing left to work with.
That is why two targets are offered above: 2 MB is the safe value, 500 KB is for when faster loading matters more than the last few percent of quality.
Keep the bottom-right corner clear
YouTube overlays the video duration in the bottom-right of every thumbnail, covering roughly 20% of the frame. Anything you put there is simply not seen.
How to do it
- Pick "Thumbnail (2 MB, 1280×720)" above, the format is already locked to JPEG.
- Drop the image in. Anything wider than 1280 px is scaled down proportionally, never cropped.
- Download and upload straight to YouTube.
Everything runs in your browser, so an unreleased video’s thumbnail never passes through anyone else’s machine.
Frequently asked questions
What is the size limit for a YouTube thumbnail?
It was 2 MB for years. YouTube raised it to 50 MB in March 2026, but that new ceiling is still rolling out account by account, so not everyone has it. Staying under 2 MB is the safe choice.
Why does my thumbnail fail to upload?
Usually the format, not the size. YouTube accepts JPG, PNG, GIF and BMP, but not WebP, which is exactly what most modern compressors output by default. That is why the output format on this page is locked to JPEG.
What dimensions should I use?
1280×720 at 16:9. That is YouTube’s recommended size and the basis for how thumbnails are scaled everywhere else. The stated minimum is 640 px wide, but that looks soft on a desktop.
Why does my thumbnail look blurry on YouTube?
Either the source was too small and got upscaled, or it was compressed too hard before upload. YouTube re-encodes what you give it to generate every placement size, so leaving some quality headroom matters. The practical sweet spot is roughly 200 KB to 1 MB.
Any layout traps?
The bottom-right corner. YouTube stamps the video duration there on every thumbnail, covering about 20% of the frame. Keep text, faces and key graphics out of it.