YouTube
Thumbnail 4K3840×2160
A 3840×2160 master of the same 16:9 frame. Upload the 1280×720 file to YouTube.
YouTube’s documented thumbnail is 1280×720, 16:9, minimum width 640, and under 2MB. 3840×2160 is the same aspect as a 4K master for your archive. YouTube displays thumbnails at 1280×720 and can reject files over 2MB, so use the HD preset for the upload.
- Export size
- 3840×2160
- Aspect
- 16:9
Source: YouTube Help — thumbnail size
How to export it
- Open the tool and drop in the photo. It stays in this browser.
- This preset is preselected. Drag the frame, or use Focus on detail, until the subject sits where you want it.
- Check any other sizes you need and download. A single size saves as a file; several sizes save as a ZIP.
Duration badge
3840×2160
What the overlay is warning you about
- Duration badge