CSS Border Radius Generator — Free Online Tool

What Is CSS Border Radius Generator?

A free online CSS border radius generator. Control each corner independently with sliders, toggle between px and % units, and preview the result live. Includes presets for circles, pills, cards, and rounded shapes.

The CSS border-radius property controls the roundness of element corners, and its versatility extends far beyond simple rounded rectangles. By adjusting each corner independently, you can create pills, circles, asymmetric shapes, and complex organic-looking forms — all with a single CSS property. CSS Border Radius Generator provides individual slider control for all four corners with a live preview that updates instantly.

Each corner — top-left, top-right, bottom-right, bottom-left — has its own slider, letting you create completely asymmetric shapes. The unit toggle between pixels (px) and percentage (%) changes the behavior significantly. Pixel values create fixed-radius corners that stay the same size regardless of the element dimensions. Percentage values tie the radius to the element size, which is how you create perfect circles (border-radius: 50% on a square).

Four presets cover the most common use cases. Circle creates border-radius: 50% for a perfect circle (or ellipse on non-square elements). Pill creates a shape with fully rounded ends (border-radius: 9999px), useful for button badges and tags. Card applies a subtle 8px rounding suitable for card components and containers. Rounded applies an 8px rounding on all corners, appropriate for buttons and form inputs.

The generated CSS code shows the shorthand syntax. If all four corners have the same value, it outputs a single value (e.g., border-radius: 8px). If corners differ, it outputs the four-value syntax in clockwise order (top-left, top-right, bottom-right, bottom-left). The code is copy-ready for your stylesheet.

Real-World Use Cases for CSS Border Radius Generator

Creating a Rounded Button with Pill Shape

Your design system uses pill-shaped buttons with 24px height and fully rounded ends. Select the "Pill" preset for border-radius: 9999px. The button preview shows the pill shape. Copy the CSS and apply it to your button component. Adjust corner values individually if you want a softer look.

Designing an Asymmetric Shape for a Hero Section

A landing page hero needs a distinctive shape: top-left at 0px, top-right at 40px, bottom-right at 0px, bottom-left at 40px. Set each corner slider independently. The preview shows a unique asymmetric shape. The generated CSS is border-radius: 0 40px 0 40px.

Making a Circular Avatar with Percentage Radius

A user avatar is a 64x64 pixel square image. Toggle the unit to % and set all four corners to 50%. The preview shows a perfect circle. The generated CSS is border-radius: 50%, which works on any square element regardless of size.

Why Use CSS Border Radius Generator?

Individual control for all 4 corners
px and % unit toggle
Live preview box
4 presets: Circle, Pill, Card, Rounded

How to Use CSS Border Radius Generator — Step by Step

Adjust sliders for each corner (top-left, top-right, bottom-right, bottom-left).

Toggle between px and % units.

Preview the border radius live.

Copy the CSS code.

Who Is CSS Border Radius Generator Best For?

UI design
button styling
card design
web development

Pro Tips for CSS Border Radius Generator

1Use pixel values for fixed-size elements (buttons, cards) where the corner radius should stay constant. Use percentage values for responsive elements where the radius should scale with the element.
2The "Pill" preset uses a very large pixel value (9999px) rather than 50% because 50% on a rectangle creates an ellipse, not a pill. The large pixel value ensures fully rounded ends on any rectangular element.
3For a "squircle" (square with slightly rounded corners popular in iOS), use approximately 10-12% border-radius on all corners. This creates a softer look than small pixel values.
4When using percentage values, the radius is calculated relative to the element's width (for left/right) and height (for top/bottom). Different percentages on horizontal vs vertical corners create elliptical corners.

CSS Border Radius Generator — Frequently Asked Questions

What is border-radius in CSS?

border-radius rounds the corners of an element. It accepts 1-4 values for each corner. For example, border-radius: 10px 20px 30px 40px sets top-left, top-right, bottom-right, and bottom-left respectively.

How to make a circle with CSS?

Set border-radius: 50% on a square element (equal width and height). This creates a perfect circle.

Will the generated CSS work in all browsers?

The CSS generators produce W3C-standard code that works in Chrome, Firefox, Safari, and Edge. Vendor prefixes are included where needed for older browser versions.

Can I copy the generated code directly?

Yes. Each generator provides a copy button that places the code on your clipboard. The code is ready to paste into your project — no cleanup or modification needed.

Is CSS Border Radius Generator really free to use?

Yes, CSS Border Radius Generator is completely free with no hidden charges, no usage limits, and no premium tiers. You can use it as often as you need without signing up or providing any personal information.

Ready to Use CSS Border Radius Generator?

Free online tool — works in your browser, no sign-up required. Start using it right now.

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