Step 1 : Go to https://www.youtube.com/, Search any video.
Step 2 : Copy the URL of the video (Example: https://www.youtube.com/watch?v=7TavVZMewpY ).
Step 3 : Paste that URL in the box given above and then click the "Get YouTube Thumbnail" button.
Step 4 : Choose your Thumbnail size acourding your wish and Download it.
1. Your custom thumbnail image should be as large as possible. It will be used as the preview image in the embedded player. Youtube recommend your custom thumbnails may Have a resolution of 1280x720 (with minimum width of 640 pixels).
2. You can upload image formats such as JPG, GIF, or PNG.
3. Your youtube thumbnail size should be remain under the 2MB limit.
4. Try to use a 16:9 aspect ratio as it's the most used in YouTube players and previews.
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