Generated CSS follows standard border-radius shorthand rules. Verify complex elliptical or blob shapes in your target browsers before shipping.

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CSS Border Radius Generator

Adjust CSS border-radius visually, preview rounded corners live, and copy ready-to-use CSS. Set each corner independently or use pill, circle, and blob presets.

Example output

border-radius: 16px;

Tailwind: rounded-[16px]

Corner values are computed locally—nothing uploaded. Add depth with Box Shadow Generator; clip custom shapes with Clip Path Generator.

Live preview

border-radius: 16px;

Preview shape
Preview color

Quick presets

Corner controls

Same on all corners
Unit
px
px
px
px

Generated CSS

CSS property
border-radius: 16px;
Tailwind
rounded-[16px]
Advanced: organic blob shapes

Dual-axis % / % syntax creates organic blobs — great for hero backgrounds and decorative shapes.

Horizontal (X)

%
%
%
%

Vertical (Y)

%
%
%
%
border-radius: 16px;
By Muhammad Abdullah Rauf · Founder, EverydayTools.proUpdated 2026-09-06· Reviewed by EverydayTools Editorial Team

What Is a CSS Border Radius Generator?

A CSS border radius generator (also called a border radius tool or rounded corners CSS generator) creates the CSS border-radius property for UI elements. Instead of typing values blindly, you adjust corners, preview the shape, and copy production-ready CSS.

The border-radius property rounds an element's corners. You can use one value for all corners, two values for opposite pairs, three values for a common pattern, or four values for each corner independently. Percentages scale with the element's size—50% on a square makes a circle.

This page is a live border radius preview and visualizer: link or unlink corners, switch units (px, %, rem, em), try pill and circle presets, or open blob mode for elliptical slash syntax. Then generate border radius CSS and copy it as a CSS declaration, Tailwind arbitrary value, inline style, or SCSS variable. Everything runs in your browser.

Use this tool when you need rounded corners CSS you can copy immediately—cards, buttons, avatars, pills, or organic blob shapes.

How to Use This Border Radius Generator

  1. Adjust the radius values

    Drag the sliders or type numbers for each corner. Start from a preset (8px, 16px, Pill, Circle) if you want a known starting shape.

  2. Link or unlink corners

    Keep corners linked for a uniform radius, or unlink to set top-left, top-right, bottom-right, and bottom-left independently (per-corner / 4 corner border radius).

  3. Preview the result live

    Watch the live border radius preview update instantly. Switch preview shapes (square, card, button, avatar), colors, and before/after to compare with sharp corners.

  4. Choose the unit

    Select px, %, rem, or em so the generated CSS matches your design tokens.

  5. Copy the generated CSS

    Copy the CSS property, radius value only, Tailwind arbitrary class, inline style, or SCSS $border-radius variable into your project.

How CSS border-radius Works

border-radius accepts length or percentage values and can use shorthand with 1–4 values. When horizontal and vertical radii differ, CSS uses a slash (elliptical / blob syntax). This generator formats simple corners into the shortest valid shorthand and outputs fancy mode as eight percentage values with a slash.

Formula

1 value:  border-radius: 16px;
           → all four corners

2 values: border-radius: 16px 8px;
           → top-left & bottom-right | top-right & bottom-left

3 values: border-radius: 16px 8px 4px;
           → top-left | top-right & bottom-left | bottom-right

4 values: border-radius: 16px 12px 8px 4px;
           → top-left | top-right | bottom-right | bottom-left

Elliptical / blob:
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  → horizontal radii / vertical radii

Assumptions

  • Corner order is always top-left → top-right → bottom-right → bottom-left (clockwise from top-left).
  • Percentages are relative to the element's box size.
  • 50% creates a circle only when width and height are equal.
  • Fancy/blob mode in this tool uses percentage radii on both axes.

Limitations

  • border-radius only rounds rectangular boxes—it is not clip-path or SVG masking.
  • This is not a complete Tailwind rounded-* scale browser; export uses arbitrary values like rounded-[16px].
  • Very large px values (e.g. 9999px) create pill ends on rectangles; they are not a separate CSS property.

Pill Buttons, Circles, and Blob Shapes

Pill buttons

Pill button CSS with a large radius

Use the Pill preset (border-radius: 9999px) for fully rounded CTA ends. A very large radius clamps to capsule ends on a rectangular button—pair with horizontal padding for classic pill shape CSS.

Avatars & icons

Circle border-radius at 50%

The Circle preset sets border-radius: 50%. On a square element (equal width and height) that produces a perfect circle. On a non-square box it becomes an ellipse.

Marketing / heroes

Blob and elliptical border radius

Advanced blob mode outputs elliptical slash syntax (horizontal % / vertical %). Soft Blob, Sharp Blob, Organic, and Random create organic CSS shapes—not SVG blob paths.

Product UI

Cards, buttons, and images

Typical cards use 8–16px. Buttons often use 8px or pill. Clip child images with overflow: hidden when rounding a card that contains media.

CSS Border Radius Examples

Card radius

Input

Modern dashboard panel

Output

.card {
  border-radius: 12px;
  overflow: hidden;
}

12px is a common SaaS card radius; overflow clips child images to the curve.

Button radius

Input

Standard UI button

Output

.btn {
  border-radius: 8px;
}

Subtle rounding that stays crisp at small sizes.

Pill button

Input

Primary CTA with fully rounded ends

Output

.btn-pill {
  border-radius: 9999px;
  padding: 0.5rem 1.5rem;
}

Matches this tool’s Pill preset—large px radius for capsule ends.

Circle avatar

Input

Square element, equal width and height

Output

.avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
}

Matches the Circle preset; unequal dimensions yield an ellipse.

Organic blob shape

Input

Decorative hero background (CSS only)

Output

.blob {
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
}

Elliptical slash syntax from fancy/blob mode—not an SVG path.

Individual corner border radius (4-value order)

Clockwise from top-left—the order this generator and CSS use.

PositionCSS corner4-value slot
Top-leftborder-top-left-radius1st
Top-rightborder-top-right-radius2nd
Bottom-rightborder-bottom-right-radius3rd
Bottom-leftborder-bottom-left-radius4th

Border radius units in this tool

Only units available in the generator UI.

UnitTypical useNotes
pxDesign-system tokens, fixed UIMost common for cards and buttons
%Circles, fluid shapesRelative to element size; 50% ≈ circle on a square
remRoot-relative scalingScales with root font size
emComponent-relative scalingScales with the element’s font size

Common border-radius values

Quick reference for typical UI patterns.

PatternCSSTypical use
Noneborder-radius: 0Tables, strict grids
Subtleborder-radius: 4pxInputs, small controls
Cardborder-radius: 12pxPanels, dashboards
Pillborder-radius: 9999pxCTA buttons, tags
Circleborder-radius: 50%Avatars on square elements
Blob30% 70% … / 30% 30% …Hero backgrounds (CSS elliptical)

Common Border Radius Mistakes

Confusing border-radius with border

border sets width/style/color of the outline. border-radius only rounds corners. Use this generator for radius—not a border-width tool.

Getting shorthand order wrong

Four values go top-left → top-right → bottom-right → bottom-left. Unlink corners here and copy the generated shorthand so the order stays correct.

Assuming border-radius: 50% always makes a circle

50% on a non-square box is an ellipse. Use equal width and height (or the Circle preset on a square preview) for a true circle.

Using unnecessarily huge values when a smaller radius is enough

For soft cards, 8–16px is usually enough. Reserve 9999px for intentional pill ends.

Mixing up % and px

px is absolute; % scales with the element. Circles and fluid blobs often need %; design tokens often use px or rem.

Reaching for clip-path when rounded corners are enough

If you only need rounded rectangle corners, stay on border-radius. Use Clip Path Generator for stars, arrows, and non-rectangular masks.

Best practices

Use consistent radius tokens across your UI

Mixing 6px, 10px, and 14px on similar components looks unintentional—pick a scale (4, 8, 12, 16) and stick to it.

Add overflow: hidden when clipping child images to rounded cards

border-radius rounds the element's border box; child images can still square off unless overflow clips them.

Use 50% for circles only on equal width and height

50% radius on a rectangle produces an ellipse, not a circle—match dimensions for avatars.

Test blob shapes in Safari and Firefox

Dual-axis percentage radii render well in modern browsers but complex blobs deserve a quick cross-browser check.

When this tool isn't the right choice

You need to format or minify an entire CSS file

Use CSS Formatter or CSS Minifier—this tool generates a single border-radius property.

You need non-rectangular clipping paths

border-radius only rounds rectangles—use Clip Path Generator for polygons and custom masks.

You need shadow depth without changing corners

Use Box Shadow Generator—radius and shadow are separate properties.

You need a full interactive button stylesheet

Use CSS Button Generator for background, padding, hover, and focus. Use this page when you only need the radius token.

Workflow guides

Step-by-step chains that connect related tools for common tasks.

Round a card, then add shadow

  1. Set border-radius to 12px or 16px with the Card preview shape and copy the CSS.
  2. Open the Box Shadow Generator to layer elevation on the same component.

Radius token → full button styles

  1. Dial in pill or 8px radius here and copy the border-radius value.
  2. Paste into a full interactive button with the CSS Button Generator when you also need hover, focus, and background.

Rounded corners vs complex masks

  1. Stay on this CSS border radius generator for rectangular rounded corners.
  2. Switch to the Clip Path Generator when you need polygons, stars, or non-rectangular masks.

When to use CSS border-radius generator vs related tools

Use this page for rounded corners CSS and border-radius export. Pair nearby design tools when you need shadows, gradients, full buttons, complex masks, or Tailwind utility lookup.

Related toolUse this tool whenUse related tool when
Box Shadow GeneratorYou need to round corners and copy border-radius CSS.Corners are set and you need offset, blur, spread, and shadow color.
CSS Button GeneratorYou only need a radius token or pill/circle preview.You want a full button stylesheet with states and backgrounds.
CSS Gradient GeneratorYou are shaping corners—not fills.You need linear, radial, or conic background gradients.
Clip Path GeneratorRounded rectangle corners are enough.You need clip-path polygons, stars, or custom silhouettes.
Tailwind CheatsheetYou already have an arbitrary rounded-[…] value from this tool.You need to look up named Tailwind utilities and CSS equivalents.

What to do next

Continue the workflow with the right follow-up tool.

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Frequently Asked Questions

What is CSS border-radius?

border-radius rounds the corners of an element's outer border edge. It accepts one to four length or percentage values (and elliptical slash syntax) and is supported in all modern browsers.

How do I make rounded corners in CSS?

Set the border-radius property—for example border-radius: 12px for all corners, or four values for each corner. This CSS border radius generator previews the result and lets you copy the CSS.

How do I set different border-radius values for each corner?

Unlink corners (turn off “same on all”), then set top-left, top-right, bottom-right, and bottom-left independently. The tool outputs four-value shorthand such as border-radius: 16px 0 0 0 for top-left only.

What is border-radius shorthand?

Shorthand lets you set multiple corners in one declaration: 1 value (all), 2 values (diagonals), 3 values (top-left | top-right & bottom-left | bottom-right), or 4 values (each corner clockwise from top-left).

What do 1, 2, 3, and 4 border-radius values mean?

1 = all corners. 2 = top-left & bottom-right, then top-right & bottom-left. 3 = top-left, then top-right & bottom-left, then bottom-right. 4 = top-left, top-right, bottom-right, bottom-left. This generator collapses to the shortest valid form when corners match.

How do I make a pill button in CSS?

Use a very large radius such as border-radius: 9999px (this tool’s Pill preset) with horizontal padding. The ends become fully rounded capsules on a rectangular button.

How do I make a circle with border-radius?

Give the element equal width and height, then use border-radius: 50% (Circle preset). On a rectangle, 50% produces an ellipse instead of a circle.

What is elliptical border-radius?

Elliptical (blob) syntax sets horizontal and vertical radii separately: four values, a slash, then four more—e.g. 30% 70% 70% 30% / 30% 30% 70% 70%. Open Advanced blob shapes in this tool to generate that CSS.

What is the difference between px and percentage border-radius?

px is a fixed length. Percentage radii scale with the element’s size—useful for circles (50%) and fluid blob shapes. Switch units in this generator to preview either.

Can I use rem or em for border-radius?

Yes. This tool supports px, %, rem, and em. rem scales with the root font size; em scales with the element’s font size.

Can I copy the generated CSS?

Yes. Copy the full border-radius declaration, the value only, an inline style attribute, an SCSS $border-radius variable, or a Tailwind arbitrary class—whichever you need.

Can I use the generated value in Tailwind?

Yes as a Tailwind arbitrary value (e.g. rounded-[16px] or a multi-corner / blob arbitrary class). This is not a full Tailwind rounded-* utility browser—use the Tailwind Cheatsheet for named utilities.

Is this border-radius generator free?

Yes. No signup required. Values are computed locally in your browser.

Does the tool run in the browser?

Yes. Corner values and previews are generated client-side—settings are not uploaded to EverydayTools servers for normal use.

Border radius generator vs CSS button generator?

This page focuses on border-radius only—corners, blobs, and shorthand export. CSS Button Generator builds full button styles (background, padding, hover, optional shadow). Use this page for radius tokens; use the button generator for a complete component stylesheet.

Privacy, accuracy, and trust

Privacy

Border-radius values are generated in your browser — corner settings are not uploaded to EverydayTools servers.

Accuracy

CSS output follows standard border-radius shorthand rules; always verify elliptical and blob shapes in target browsers.

For design and prototyping — align final radius tokens with your design system in production.

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Reviewed by EverydayTools Editorial Team on 2026-09-06.

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