If you're looking to download a YouTube thumbnail, there are a few things you need to know. YouTube thumbnails are typically 160x90 pixels but can be as large as 1920x1080 pixels. They can be in .jpg, .png, or .gif format.
To download a YouTube thumbnail, first find the URL of the video you want to download and paste the URL in the input box above. You can then right-click on the thumbnail and select "Save Image As..." to save it to your computer.