Guide
YouTube thumbnail sizes in 2026
Studio asks for 1280×720. The CDN then publishes a small family of files, not a 4K master. This is the chart the size checker measures against.
What you should upload in YouTube Studio
YouTube’s own creator docs still center on a 1280×720 JPEG, GIF, or PNG, 16:9, under 2 MB. That is the working size for click-through on TV, desktop, and the mobile home grid. You can upload 1920×1080; do not assume viewers receive 1920×1080 as the public still. The file people and this downloader see is usually maxresdefault.jpg at 1280×720.
Minimum width YouTube will even consider is 640 pixels. Below that, Studio refuses the custom upload and you live on auto stills.
What YouTube publishes on the CDN
| File | Typical pixels | Notes |
|---|---|---|
maxresdefault.jpg | 1280×720 | Custom 16:9 HD. Often missing on older or auto-only videos. |
hq720.jpg | 1280×720 | Common HD fallback when maxres is absent. |
sddefault.jpg | 640×480 | 4:3. Letterboxing is normal. |
hqdefault.jpg | 480×360 | The file that almost always exists. |
mqdefault.jpg | 320×180 | 16:9 small. Fine for lists. |
default.jpg | 120×90 | Original player icon size. |
0.jpg–3.jpg | 480×360 | Auto-generated frames. |
maxresdefault.webp | 1280×720 | Under /vi_webp/ when published. |
Generate live URLs with the URL generator. Save them with the HD downloader.
When HD is missing
If maxresdefault.jpg 404s or returns a 120×90 placeholder, the video does not have that file. Do not label an upscaled HQ still as UHD. Use hq720.jpg next, then SD, then HQ. The UHD reality page is the longer version of this paragraph.
Shorts thumbnail size
Shorts use the same filenames. The player is 9:16; the custom upload is still 16:9. Design the center column. Details: Shorts thumbnails.
Width and height to put in HTML
If you hotlink or self-host a still, match the real pixels so the browser does not layout-shift:
<!-- HD when maxres is live -->
<img src="https://i.ytimg.com/vi/VIDEO_ID/maxresdefault.jpg" width="1280" height="720" alt="">
<!-- Fallback that almost always exists -->
<img src="https://i.ytimg.com/vi/VIDEO_ID/hqdefault.jpg" width="480" height="360" alt="">Do not set width="3840" on a 1280 file. That only stretches HQ mush. Probe first with the thumbnail size checker.
Upload checklist in YouTube Studio
- 1280×720, 16:9, under 2 MB
- Face and 1–3 words in the center (phones crop edges)
- Readable at about 120 pixels wide — that is search-grid size
- Does not promise a 4K still just because the video is 2160p