YouTube Thumbnail - Check & Resize Your Image
Check your YouTube video thumbnail image locally, compare measured fields with the dated source, then crop or pad to the recommended canvas and recheck the output.
The original stays on your device. EXIF orientation may be applied by the browser; output is a new PNG.
Recommended export: 3840 × 2160 px. This is a recommendation, not an invented minimum.
Source, scope and uncertainty
Official YouTube video thumbnail source · checked 2026-10-25 · custom video thumbnail; upload-device limits differ.
Primary source re-read 2026-10-25: “Have a resolution of 3840 x 2160 pixels for videos ... with a minimum width of 640 pixels for videos and a minimum height of 640 pixels for Shorts. Be uploaded in image formats such as JPG or PNG. Remain under MB limits ... Mobile: 2 MB for video thumbnails or 10 MB for podcasts. Desktop: 50MB for video, Shorts, and podcast thumbnails.” YouTube writes MB without defining it; the tool counts 1 MB as 1,000,000 bytes, the stricter reading (a 2,000,000 B file passes, 2,000,001 B fails). Checks turn to UNKNOWN again 30 days after this date unless the source is read again.
Desktop and mobile have different upload limits. The 3840 × 2160 canvas is a recommendation; account eligibility is not checked locally.
PASS/FAIL applies to the stated measurable fields. ADVISORY describes a recommendation. UNKNOWN remains unknown; a local pass cannot promise upload acceptance.