YouTube thumbnail sizes explained: maxresdefault, sddefault and more
Every YouTube video has several thumbnail files stored under the same video ID. They follow a fixed pattern, img.youtube.com/vi/VIDEO_ID/NAME.jpg, where NAME is the version you want. That is how ThumbGrab finds every size from a single link.
The five standard versions
- maxresdefault: 1280×720 pixels, 16:9. The largest version, and the one most people want.
- sddefault: 640×480 pixels, 4:3.
- hqdefault: 480×360 pixels, 4:3. This one exists for almost every video.
- mqdefault: 320×180 pixels, 16:9. A small version without black bars.
- default: 120×90 pixels, 4:3. The tiny preview used in small lists.
Why some versions have black bars
Most YouTube videos are 16:9, but sddefault, hqdefault and default are 4:3. To fit a widescreen picture into a squarer frame, YouTube adds black bars above and below it. The image itself is not cut off, it is just smaller inside the frame. If you want a clean widescreen picture from one of these files, you will need to crop the bars away, which also costs you some resolution.
maxresdefault and mqdefault are true 16:9 files, so they have no bars and need no cropping.
Why the largest size is sometimes missing
YouTube only creates maxresdefault when the thumbnail it has is big enough to make a 1280×720 version. Older videos, videos uploaded before HD thumbnails were common and videos whose creator chose a small custom image often stop at sddefault or hqdefault. When this happens, the largest version simply doesn’t exist, and no tool can create it without enlarging a smaller picture, which looks soft.
Which size should you pick?
- Blog posts, slides and reference boards: maxresdefault, because it is sharp and has the right shape.
- Analysis and side-by-side comparison: maxresdefault again, so every image has the same proportions.
- Small cards and lists: mqdefault is usually enough and loads fast.
- When maxres isn’t available: sddefault is the next best choice, then hqdefault.
Other files you may come across
You may also see numbered files such as 1.jpg, 2.jpg and 3.jpg in the same folder. These are small frames taken from the video itself rather than the thumbnail the creator chose, so ThumbGrab doesn’t list them.
How to get every size at once
You don’t have to build these addresses by hand. Paste a video link into ThumbGrab and it shows each version that exists as a preview card with its resolution, so you can compare them and download the one you need. Remember that thumbnails are the work of their creators, so read our guide on reusing thumbnails before publishing one.