Free YouTube Thumbnail Resizer
Make your thumbnail fit a 16:9 frame. Start at 1280 x 720, or choose a larger size when your source image has enough detail.
Free to use. No signup. No watermark. Your images stay in your browser.
Your image
No image selected.
Your preview will appear here.
Position your crop
Drag the image or use the sliders to keep your subject in view. Then create your image to save this crop.
Preview fits this space. View at 100% to check the pixels.
Your image stays on this device. We do not upload it.
Image settings
Output limit: 4,096 px per side and 16 million pixels.
Choose an image to get started.
Your image is ready.
Download imageUse Mallary to share your next post.Your image is ready.
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From this tool to your next post
Pair your thumbnail with a video in Mallary. Manage the YouTube upload and your other social posts from the same place.
The thumbnail file does not become a video. Prepare a separate image post if you also want to share the artwork on other networks.
Reduce the thumbnail file size- Download a JPG or PNG thumbnail within the 2,000 KB target.
- Add your video to Mallary and attach the image as its thumbnail.
- Review your YouTube post, then publish or schedule the video.
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Choose a size for your video thumbnail
Choose a setting here, then check your image in the editor.
| Setting | When to use it |
|---|---|
| A 1280 x 720 thumbnail 1280 x 720 px | Use a smaller 16:9 canvas when your source has limited detail or a larger file is not needed. |
| A 1920 x 1080 thumbnail 1920 x 1080 px | Keep more pixels from a clear source while using the same 16:9 shape. |
| A 3840 x 2160 thumbnail 3840 x 2160 px | Use YouTube's current recommended video-thumbnail dimensions when your source is large enough. Check file size too. |
YouTube Studio. YouTube recommends 3840 x 2160 for regular video thumbnails and accepts JPG or PNG. Its native upload limits differ: 2 MB for video thumbnails on mobile and 50 MB on desktop. YouTube thumbnail size and upload limits Checked .
YouTube API. The thumbnail upload API has a separate 2 MB limit. A larger file that works in desktop YouTube Studio can still be too large for an API upload. YouTube API thumbnail upload Checked .
Publishing with Mallary. Choose JPG or PNG and a Maximum file size of 2,000 KB as a safe target for Mallary. Add the image as a thumbnail on a video; an image alone is not a YouTube video.
See what Fit and Fill change
We resized this illustration with the same tool above. Fit keeps the full picture. Fill crops the edges to cover the frame.
1280 x 720 px. PNG lossless encoding. White background. The examples use the tool's default image size.
These are smaller previews of real exports from this tool. Sizes above describe the full files. Your result depends on your source image and settings.
A few things to know.
YouTube's current help page recommends 3840 x 2160 for video thumbnails. The default here is a smaller 1280 x 720 option with the same 16:9 shape.
Use large, clear text in your source image. A thumbnail needs to make sense when shown at a small size.
For video thumbnails uploaded directly to YouTube Studio, YouTube lists a 2 MB limit on mobile and a 50 MB limit on desktop.
Mallary uploads thumbnails through the YouTube API, which has a separate 2 MB limit. Choose JPG or PNG and set Maximum file size here to 2,000 KB or less. A thumbnail must be attached to a video.
Platform guidance: YouTube: Custom thumbnail sizes and file limits · YouTube API: Thumbnail upload formats and limit
Your questions, answered.
Is 1280 x 720 the only YouTube thumbnail size?
No. It is a smaller 16:9 preset. YouTube's current help page recommends 3840 x 2160 for video thumbnails. Choose the larger option when your source has enough detail.
Can I use a wide thumbnail for a YouTube Short?
Use a tall 9:16 image for a Short. YouTube recommends 2160 x 3840. Select Custom size, turn off Keep this shape, and enter those dimensions when your source has enough detail. The listed wide presets are for regular video thumbnails.
What if my resized thumbnail is too large to upload?
Choose JPG or PNG and enter a Maximum file size. Use 2,000 KB or less for Mallary or mobile YouTube uploads. YouTube Studio on desktop allows up to 50 MB, but its API has a separate 2 MB limit. A smaller file limit may reduce quality or dimensions, so check the result.