Free YouTube thumbnail tester

Preview and test your YouTube thumbnail before you publish

See it in a real YouTube feed, among the videos it will compete with. Then get an AI critique with a 0–100 score, compare two options, and improve it — or generate a new one from your video.

Open the preview tool

Five tools, one thumbnail workflow

Use one or use them all. Each step answers the question the last one raised.

1See it

Check it at every size a viewer meets it, next to the videos it is up against.

Preview

Free · unlimited · no sign-up

Type the title you plan to publish with and your thumbnail lands in a feed built from the videos actually ranking for it — so “does it stand out?” is answered against the row it will really appear in.

  • Homepage
  • Search
  • Sidebar
  • Mobile
  • Tablet
  • TV
  • Channel page
  • Two titles previewed at once
  • How it reads with colour vision deficiency
  • YouTube's size and file limits, before you upload
Preview your thumbnail

2Score it

An honest read before you commit — what works, what doesn't, and which option wins.

Critique

5 free a month · no sign-up

A 0–100 score across ten judged dimensions, and up to three concrete fixes — in seconds.

Get a critique

Compare

Uses 2 of your critiques

Two thumbnails, one verdict: full critiques of both, a winner with a confidence, and the differences that decide it.

Compare two thumbnails

3Fix it

Turn the critique into a better thumbnail, or start fresh from the video.

Improve

3 free a month · no sign-up

Pick the fixes from its critique and AI edits your actual image — same subject, same face — into an improved 1280×720 version.

Improve a thumbnail

Generate

3 free a month · sign in

Paste a video link — or describe a video you haven't uploaded yet — and AI designs a 1280×720 thumbnail built from your video, not a prompt, then scores it.

Generate a thumbnail

Then take the new version back to Preview and check it again.

More tools: breakout thumbnail search · YouTube thumbnail downloader · thumbnail resizer

Start with a free preview

No sign-up. Drop in a thumbnail, add your title, and see it where your viewers will.

Open the preview