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Free YouTube Thumbnail Grader

Upload your thumbnail and get an instant AI-powered score with improvement suggestions.

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PNG, JPG, or WebP — max 5 MB

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YouTube Thumbnail Best Practices

Your thumbnail is the first thing viewers see, so clarity at small sizes matters. Use contrast, simple composition, readable text, and an emotional focal point to make the promise of the video easier to understand.

The Rules That Matter Most

  • Short text overlay so the idea is readable on mobile
  • Face fills 40-60% of the frame when present
  • Strong contrast between the subject, background, and text
  • Few visual elements so the thumbnail does not feel crowded
  • Test at 160x90px — that's how it appears on mobile

Pair your thumbnail with a high-impact title for maximum CTR. Try our free Title Analyzer or read our full Thumbnail Best Practices guide.