What Size Is a YouTube Thumbnail? (2026 Guide)

YouTube’s official recommendation is 1280×720 pixels, a 16:9 aspect ratio, as JPG, GIF, PNG or WebP, under 2MB. That is the number to design against for a standard horizontal video, and it is what gets used whenever YouTube needs a large preview — the watch page sidebar on some layouts, and social share cards when a video link is pasted elsewhere.

You do not have to hit 1280×720 exactly. YouTube accepts anything at the 16:9 ratio and re-encodes it, but designing at the native resolution avoids YouTube’s own scaling softening fine detail, especially text.

The 1280×720 master gets shrunk everywhere it actually appears. In the home feed and search results on desktop it renders around 246×138px; on mobile, closer to 180×101px. That is a roughly 85% reduction from the file you uploaded, and it is the gap that causes most thumbnail failures: text and details that read clearly at full size disappear entirely at feed size.

Design for the smallest size first, not the largest. If a thumbnail is not legible shrunk to postage-stamp size on a phone screen, it will not perform, no matter how good it looks in your editor at 100% zoom.

Shorts covers are vertical, 9:16, ideally 1080×1920px. A horizontal thumbnail cropped down to a vertical frame almost always loses the subject or the text — Shorts covers need to be composed vertically from the start, not repurposed from a horizontal thumbnail.

Every uploaded video gets several auto-generated thumbnail sizes in addition to whatever custom thumbnail you set: a 120×90 default, a 320×180 medium (mqdefault), a 480×360 high (hqdefault), a 640×480 standard (sddefault), and — only for videos uploaded in HD — a 1280×720 max-res (maxresdefault). Older or lower-resolution uploads may not have the max-res version.

That is also why a thumbnail downloader works at all: those files sit at predictable URLs on YouTube’s image CDN for every public video, custom thumbnail or not.

Canvas at 1280×720, 16:9. Keep the subject and any text inside the middle ~80% of the frame — the outer edge can get cropped or obscured by the video-length badge in some layouts. Cap overlay text at 2–4 words in a heavy weight; anything smaller than roughly 60pt at full canvas size tends to vanish at feed resolution.

Export as JPG or WebP for smaller file size (PNG only if you need transparency, which YouTube flattens anyway), stay under YouTube’s 2MB cap, and preview the result shrunk to feed size — not just full-screen in your editor — before you publish.