YouTube thumbnail tester

1. 1

   Add a thumbnail

   Drop a PNG or JPG. It's read in the browser and isn't uploaded.

2. 2

   Type the title

   Enter the title, channel name and video length. Titles past two lines are cut off as on YouTube, and the counter shows the 100-character limit.

3. 3

   Switch layouts

   Look at the home feed, search results, the up next sidebar and a phone, and read the upload check under the form.

The sidebar is the hardest test: there the thumbnail is about 168 pixels wide. If you can't read its text or tell what it shows at that size, viewers scrolling past can't either.

• The length badge sits on the bottom right corner in every layout, so keep faces and text out of it.
• Titles stop after two lines on the home feed, in search and in the sidebar. Put the words that matter first.
• Next to the grey stand-ins, check that the thumbnail stands out by its colours and shapes alone.

YouTube recommends 3840 × 2160 pixels at 16:9, at least 640 pixels wide, as a JPG or PNG. A thumbnail uploaded from a computer can be up to 50 MB; from the mobile app, 2 MB.

Custom thumbnails need a verified account. For a Short, the thumbnail is vertical instead: see the YouTube Shorts thumbnail guide.

They're close to what YouTube shows in a desktop browser about 1440 pixels wide and on a phone. YouTube resizes its grid with the window, so the real sizes move a little.

It isn't 16:9. YouTube shows a thumbnail in a 16:9 frame, so crop it to 16:9, for example 1920 × 1080 or 3840 × 2160.

No. It shows how a thumbnail looks. To compare click-through rates on real viewers, use Test & Compare in YouTube Studio.

No. The image is read in your browser and never leaves your computer.