Tool World

Border Radius Generator

Generate CSS border radius with visual preview

This Border Radius Generator allows users to precisely define and visualize custom rounded corners for web elements. By inputting specific pixel values for Top Left (px), Top Right (px), Bottom Right (px), and Bottom Left (px), the tool instantly calculates and displays the corresponding `border-radius` CSS property. This functionality simplifies the process of creating complex or asymmetrical corner designs, providing an immediate visual preview of the resulting shape. The tool is invaluable for UI designers, web developers, and front-end engineers who need to implement precise visual aesthetics in their projects. It eliminates the guesswork and manual adjustments typically required to achieve specific rounded corner effects, ensuring design accuracy and significantly speeding up development workflows. Users can experiment with different radius values to find the perfect aesthetic without repeatedly editing CSS files and refreshing a browser. Upon generating the `border-radius`, the tool provides several key outputs. The `CSS Border Radius` is the exact CSS code snippet ready for integration into stylesheets. The `Uniform Corners` output indicates whether all four specified corners share the same radius value, offering quick insight into the symmetry of the design. Finally, the `Shape Type` describes the overall geometric characteristic of the generated border, such as "rounded rectangle," "ellipse," or "custom shape," helping to categorize the visual outcome.

Inputs

Provide the following 4 values to run the Border Radius Generator:

  • Top Left (px) [number] — default 8
  • Top Right (px) [number] — default 8
  • Bottom Right (px) [number] — default 8
  • Bottom Left (px) [number] — default 8

What it calculates

This tool returns:

  • CSS Border Radius — primary result
  • Uniform Corners
  • Shape Type

Worked example

For the sample inputs below:

  • Top Left (px): 8
  • Top Right (px): 8
  • Bottom Right (px): 8
  • Bottom Left (px): 8

the Border Radius Generator produces:

  • CSS Border Radius: 8px
  • Uniform Corners: Yes
  • Shape Type: Rounded

How it works

The result is derived through the following steps:

  1. isUniform = topLeft === topRight && topRight === bottomRight && bottomRight === bottomLeft
  2. css = isUniform ? `${topLeft}px` : `${topLeft}px ${topRight}px ${bottomRight}px ${bottomLeft}px`
  3. shape = isUniform && topLeft > 50 ? 'Pill/Circle' : isUniform ? 'Rounded' : 'Custom'

Frequently Asked Questions

What is a border radius generator?

A border radius generator is a tool that allows designers to create and customize CSS border radius values visually, with instant previews.

How do I use the Border Radius Generator?

Simply adjust the slider or input your desired pixel value for each corner of your element to see a live preview and the corresponding CSS code.

Are there any browser compatibility issues with border radius?

Most modern browsers support border radius properties. However, for older browsers, ensure that you include vendor prefixes like -webkit- or -moz-.

Can I copy the CSS code directly from the tool?

Yes, you can easily copy the generated CSS code from the tool for use in your web projects.

Is there a limit to how many corners I can adjust?

No, you can adjust the border radius for all four corners independently, providing maximum customization for your designs.