YouTube thumbnail sizes, and why HD is sometimes missing
We checked which thumbnail sizes YouTube serves for 12 videos from 2005 to 2017: which exist, why two have black bars, and the grey image you get instead of HD.
We checked which thumbnail sizes YouTube serves for 12 videos from 2005 to 2017: which exist, why two have black bars, and the grey image you get instead of HD.
You want a video's cover image at full size: to study a competitor's thumbnail, to put your own old cover in a deck, or to check how a design reads small. YouTube keeps every cover at fixed addresses in several sizes, but not every video has every size. On November 6, 2026 we checked 12 public videos uploaded between 2005 and 2017 to see which sizes actually exist.
Each video's cover lives at i.ytimg.com/vi/ followed by the video id and a file name. These are the ones that matter:
The two with black bars surprise people. If you want a clean 16:9 picture, take 1280 × 720, or 320 × 180 if small is enough.
For each of the 12 videos we requested every size and read the size of the picture that came back.
The videos we can name without sending traffic to anyone's music: YouTube's first upload, "Me at the zoo" from 2005, has only the three smaller sizes. A 2013 Google for Developers talk on the embedded player has all five.
When a size does not exist, YouTube still answers. It sends an error code with a small grey 120 × 90 placeholder. A browser shows that picture as if nothing were wrong, and a downloader that only builds the address and saves the file gives you a grey square named maxresdefault.jpg.
So check what you saved. If the file is tiny and grey, that size does not exist for the video. Take the next size down.
It is free, needs no account, and nothing is uploaded. The download passes through this site only so your browser can save it as a file.
A thumbnail belongs to the channel that made it. Saving one to study what works, or to get back your own old cover, is the common use. Putting another channel's thumbnail on your own video is not, and YouTube can remove it under its copyright rules.
If you are working on your own cover, two other free tools help. The thumbnail tester shows your image and title as a YouTube card on the home grid, in search and on a phone, before you upload. That is where the 320 × 180 size matters: it is close to how big a cover looks in a phone feed. To make a new cover from a description, the AI thumbnail maker draws a 1280 × 720 image from a prompt, for credits.