Privacy Policy

Thumb Checkup is a browser-based thumbnail tester. It is built so you can preview a thumbnail and title without creating an account or uploading the image to a server.

Image processing

Your thumbnail image is read by your browser and rendered on your device. The image is not uploaded to Thumb Checkup, Cloudflare, or any application server by this tool.

Inputs

The title, channel name, duration, preview theme, and device width controls are used in your browser to update the preview. Thumb Checkup does not run a backend database for these inputs.

Local checks

The brightness, contrast, color energy, dominant color, title clipping, and small-detail checks are calculated locally in your browser from the image and layout currently on the page.

Third-party advertising

Thumb Checkup may add third-party advertising in the future. If ads are added, the advertising provider may use cookies or similar technologies according to its own policies. The thumbnail tester itself will still be designed to keep image processing in your browser.

Contact

Questions about this policy can be sent to lincyang85@gmail.com.