IMAGE TOOL
Thumbnail Readability Checker
Check whether your YouTube thumbnail stays readable on a smaller screen.
FreeNo sign-upProcessed in browser
YouTube Thumbnail Readability Checker
Check resolution, 16:9 ratio, text size, density, edges, and safe area. It does not predict CTR or give a design score.
Drop a thumbnail here or choose an imageJPG · PNG · WebP supported
Selected thumbnail
Analyzing
Analysis complete
Select a result to show its related area on the original image.
Original and safe area
Results
THUMBNAIL GUIDE
What is a thumbnail readability checker?
It scales down your upload and checks YouTube-oriented image size, aspect ratio, detected text size, density, and edge placement. It does not judge your design or predict clicks.
Why check a mobile preview?
Thumbnails are often seen at a small size. Text that looks large in the original can be hard to read after scaling, so review the mobile preview before publishing.
Safe area and text contrast
Elements near the edge can feel cramped across layouts. Contrast guidance is a pixel-based heuristic, not a WCAG pass/fail result or an absolute quality score.
Frequently asked questions
Is my thumbnail uploaded to a server?
No. Image analysis and OCR run in your browser, and BaroTool does not store your image.
Can it check Korean and English?
Yes. It detects text areas in thumbnails containing Korean, English, or both.
Does it predict CTR?
No. It only reports observable readability signals such as small text, edges, and safe area.
What thumbnail size does YouTube recommend?
1280 × 720 at a 16:9 ratio is generally recommended.