Corner Design is a visual tool for debugging and designing CSS border-radius and corner-shape properties.
Instantly preview and adjust superellipse() parameters with interactive sliders. Once you are satisfied with the result, simply click the copy button ❐ to grab the generated CSS code and use it anywhere in your project.
A superellipse (also called Lamé curve or squircle) is a mathematical shape between an ellipse and a rectangle. It creates smoother, more organic-looking corners than standard CSS border-radius — similar to Apple's iOS app icons.
Corner Design was created by Dufran, an indie developer passionate about building useful tools for the web community.