Turn any image into a compact 16:9 thumbnail

YouTube currently recommends 3840×2160 pixels at a 16:9 ratio, with a minimum width of 640px, and its Help page lists JPG or PNG uploads. Its video-thumbnail size limit is 2MB when uploading from mobile and 50MB from desktop. This tool's 1280×720 JPEG output is a smaller compatible export, not the current recommended maximum.

Check the limit for the device you are using: 2MB for a video thumbnail uploaded from mobile and 50MB from desktop. Then check that the upload is JPG or PNG and that custom thumbnails are enabled for the account. Kabo may accept a WebP or GIF source, but it always converts the successful result to a JPG under the smaller mobile cap; it cannot change account eligibility.

Photos: crop to fill, then drag and scale until the subject sits where you want it. Graphics with text or logos: fit inside if cropping would cut something, though redrawing the graphic at 16:9 beats bars. Bars are a fallback, not a look.

Yes, downscaling removes pixel detail, and 1280×720 is below YouTube's current 3840×2160 recommendation. The tradeoff is a compact file that clears the 2MB mobile limit. This tool starts at 92% JPEG quality and only steps down if needed; the readout tells you exactly what quality you received.

No — the whole pipeline (decode, resize, compress) runs in your browser with the canvas API. Nothing leaves your device, which is also why it works offline once the page loads. Same privacy stance as our Thumbnail Preview tool.

Technically yes — grab one with our Thumbnail Downloader for reference or research. But reuploading someone else's thumbnail as your own is a copyright problem, not a size problem. Resize your own art; study theirs.