Best Image Sizes for a YouTube Thumbnail
Use YouTube’s current 16:9 recommendation, keep the file under the upload limit, and resize in your browser if the image is the wrong shape.
Updated 14 November 2026. Platform sizes can change; check the official help page we link to if you are publishing today.
This guide uses the free Image Resizer. The file or text stays in your browser.
The official size, not a recycled 1280 × 720 rule
Many older articles still say a YouTube thumbnail should be 1280 × 720 pixels. That size is 16:9 and is still accepted. On 14 November 2026, YouTube’s help page Add custom thumbnails on YouTube recommended a larger image:
| Type | Recommended size | Minimum | Aspect ratio |
|---|---|---|---|
| Video thumbnail | 3840 × 2160 | 640 pixels wide | 16:9 |
| Shorts thumbnail | 2160 × 3840 | 640 pixels tall | 9:16 |
| Podcast playlist thumbnail | Use a square image | — | 1:1 |
File limits on that page: 2 MB for a video thumbnail uploaded from a phone, 10 MB for a podcast thumbnail from a phone, and 50 MB for video, Shorts and podcast thumbnails from a computer. Formats include JPG and PNG. Custom thumbnails need a verified account.
1. Start with the right shape
For a standard video, design in 16:9. If you upload a different ratio, YouTube may add bars or scale the image. Keep important text and faces toward the center; the thumbnail is often seen as a small preview.
2. Resize the image
- Open the Image Resizer and choose your image. Nothing is uploaded to ToolVerse.
- Use the 3840 × 2160 preset for a video thumbnail, or 1920 × 1080 or 1280 × 720 if a 4K image is slow on your phone. Each of those is 16:9.
- For a Shorts thumbnail, set 2160 × 3840 (or another 9:16 size).
- Turn off “Keep original aspect ratio” only if you are sure you want the exact frame; otherwise the picture may stretch. It is usually better to crop in an editor first, then resize.
Very large images can be slow or can fail on phones with little memory. If that happens, use 1920 × 1080 and export a JPG.
3. Keep the file under the upload limit
If you will upload from a phone, a 3840 × 2160 PNG can go over 2 MB. In that case, download a JPG from the resizer, or run the file through the Image Compressor until it is under 2 MB, then check that the text on the thumbnail is still readable.
4. Upload it in YouTube Studio
In YouTube Studio, open the video, choose the custom thumbnail upload, and save. Changes can take a while to show everywhere. This guide does not promise more views; it only helps you meet the current size and format rules.