Test a thumbnail where it becomes small
The Composition Desk creates a local visual study from your image. Its duration, hover-action and edge reserves are simulations, not certified dimensions for every YouTube layout.
Open the local toolStart with the focal point
The main 1280 by 720 study center-crops to 16:9 without stretching. Check that the subject and important words survive that crop before adjusting any overlay. The original file stays unchanged.
Change the viewing conditions
- Adjust the duration width and edge margin rather than assuming one fixed safe zone.
- Look at the 168-pixel-wide preview. Read the words and identify the focal point yourself; no readability score is invented.
- Compare the 4:5 center crop to see which edges disappear. It cannot predict the image generated from a vertical video.
Keep a study separate from the upload
The exported PNG contains the working canvas and selected guides. It is an annotated study, not a guaranteed upload-ready thumbnail. Check the platform's current upload size and file limits for your device before publishing.
References used by the tool
Keep the limit in view
Overlay positions vary across layouts, devices and states. An adjustable composition study cannot guarantee that every viewer sees every word.