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Border Radius Generator

Border Radius Generator

Visually craft CSS border-radius values — including the 8-value slash syntax for organic blob shapes

Corner settings

Presets:

Examples

Pill button

border-radius: 9999px;

Setting an extremely large radius on all corners produces a fully rounded pill shape that adapts to any element size.

Organic blob

border-radius: 60% 40% 30% 70% / 60% 30% 70% 40%;

The slash syntax lets each corner have a different horizontal and vertical radius, creating the fluid, amoeba-like shapes popular in modern UI design.

Details

The CSS border-radius property accepts up to eight values using the slash syntax (a b c d / e f g h) that controls horizontal and vertical radii independently for each corner — unlocking organic blob shapes and asymmetric curves. This generator lets you dial in all four corners with sliders in px or %, toggle advanced mode for separate horizontal/vertical radii, see the shape update in real time, and copy the finished CSS rule. Everything runs locally in your browser.

About this tool

Create CSS border-radius values visually with live preview, custom corner controls, blob shapes, and one-click copy. Free online generator. Border Radius Generator runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

What this tool does not do

  • Border Radius Generator is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

How do I use this tool?

  1. How do I use Border Radius Generator?

    Open Border Radius Generator, enter or paste your input, and copy the result. The page works without an account.