Check your YouTube thumbnail before you upload
Free checks: size, contrast, phone-size text, timestamp corner, feed preview.
Runs in your browser. Your image is never uploaded.
or drag and drop it here, or paste it (Ctrl/⌘+V). JPG or PNG.
What it checks
- Size, shape and file: 16:9, at least 1280×720 (YouTube's minimum width is 640), and under 2 MB for phone uploads.
- Contrast and brightness: the WCAG luminance contrast between the darkest and lightest areas, plus overall brightness and colourfulness.
- Text size: shows your thumbnail at true phone sizes (168×94 and 246×138) and measures how much detail survives.
- Timestamp corner: overlays the duration badge and warns if busy detail sits under it.
- Feed preview: desktop home, mobile and search mock-ups, in light and dark mode, with your own title.
No "viral score": no tool can predict views from pixels. These are clear, explained checks you can act on.