Paste your thumbnail text. Find out whether it's short enough, readable at phone-feed size, and specific enough to create click intent — before you design.
Readable
The viewer should understand the text at phone-feed size.
Different
Add a second angle instead of repeating the title.
Specific
Use concrete words, numbers, mistakes or outcomes.
The best thumbnail text is short enough to scan in a feed and different enough to support — not repeat — the title.
Readable
The viewer should understand the text at phone-feed size.
Different
Add a second angle instead of repeating the title.
Specific
Use concrete words, numbers, mistakes or outcomes.
Scores are directional readability signals.
Thumbnail text is read in a fraction of a second, at the size of a fingertip. Its job isn't to repeat the title — it's to add the emotion, the stakes or the tension that makes the title worth clicking.
Title and thumbnail are read together. If they say the same thing, you've wasted one of them. Let the title carry the topic and the thumbnail carry the feeling.
Title: How I Budget My Money — Thumbnail: HOW I BUDGET
Title: How I Budget My Money — Thumbnail: "I was broke"
More words means smaller type, and small type disappears in a phone feed. If you need a sentence, it belongs in the title.
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Thick font, high contrast against the image, and nothing important in the bottom-right corner, where YouTube shows the video length.
Thin white text over a bright sky, bottom-right corner
Heavy outlined text, top-left, over a plain area of the image
A number or a result on the thumbnail has to show up in the video. Viewers who feel tricked leave fast.
$10K/MONTH (for a video that never mentions income)
[your real result] — or a question like "WORTH IT?" when you don't have one
Rewrites are illustrative examples, not measured results.
Usually two to four. Fewer words means larger type, which is what survives in a mobile feed.
It should support the title without repeating it — the title explains the topic, the thumbnail adds the emotion or tension.
Yes, no sign-up, with a small hourly limit. It measures length and phone-size readability and gives AI feedback and three alternative texts.
This checker reads the text only. For a review of the image itself, use Thumbnail Studio.