Preview your thumbnail as it will look on YouTube
Drop up to four thumbnail candidates and see them in the home feed, search results, watch-page sidebar and the mobile app, in light and dark mode. Blur them for a squint test, shrink them to feed size, and pick the one that wins.
Ideally 1280x720 JPG or PNG. Add several versions to compare them.
Your candidates
How to test a YouTube thumbnail
- Add your candidatesDrop one thumbnail, or several versions you are choosing between.
- Set the contextType your real title and channel name. Switch to dark mode, since most viewers use it.
- Judge at feed sizeLook at the sidebar and mobile mockups, run the squint test, and keep the version that still reads clearly.
Frequently asked questions
Why preview a thumbnail before uploading?
On YouTube your thumbnail is usually shown small, next to competing videos, and often in dark mode. Details that look great at full size can vanish at 168 pixels wide. Previewing shows what viewers actually see and helps you pick the version that reads best.
What is the squint test?
Blurring the thumbnail simulates a quick glance or a tiny screen. If the main subject, contrast and any large text still stand out when blurred, the thumbnail will work in a crowded feed.
Are the mockups exact copies of YouTube?
They mirror the proportions and typography of the current YouTube layouts closely enough to judge a thumbnail, but they are generic mockups built here, not YouTube's own interface, and YouTube changes its design regularly.
Are my images uploaded?
No. The images are displayed straight from your device with a local object URL. Nothing is sent to a server.