Your thumbnail is the single biggest factor in whether someone clicks your video, so it needs to be sharp, correctly sized, and within YouTube's limits or the upload simply fails. Here's the exact spec and how to hit it every time.
The official spec
| Attribute | Requirement |
|---|---|
| Resolution | 1280×720 px (minimum width 640 px) |
| Aspect ratio | 16:9 |
| Max file size | 2 MB |
| Formats | JPG, PNG, GIF, BMP |
| Recommended | JPG ~90% quality for photos; PNG for text overlays |
Make one in seconds
- Open our YouTube Thumbnail Resizer.
- Upload any image — it's cropped and resized to exactly 1280×720.
- Download it, ready to upload with your video.
If your thumbnail file is over the 2MB limit, run it through Compress Image to 200KB first, or convert it to JPG — a 1280×720 JPG at ~90% quality is well under the limit and stays crisp.
Frequently asked questions
- What is the correct YouTube thumbnail size?
- 1280×720 pixels at a 16:9 aspect ratio, with a minimum width of 640 px, saved as JPG, PNG, GIF or BMP and kept under 2MB.
- Why does YouTube reject my thumbnail?
- Almost always because the file is over the 2MB limit, or the width is under 640 px. Compress the image or resize it to 1280×720 and try again.
- Should a YouTube thumbnail be JPG or PNG?
- JPG is best for photographic thumbnails (smaller file); PNG is better when you have crisp text overlays or graphics that must stay sharp.