Border Radius Generator
The Border Radius Generator is a free online tool that helps you create custom CSS border-radius values with a visual interface. It is ideal for frontend developers and designers who need to round corners, create circles, or design complex shapes. Use it to instantly generate the correct CSS syntax for any element.
How the Border Radius Generator works
- 1
Add Your Content
Use the four sliders to set a percentage radius for each corner independently, from 0 to 100.
- 2
Format Your Data
The tool builds the full eight-value border-radius shorthand (horizontal and vertical radii around the slash) and morphs a live preview box as you drag.
- 3
Get Your Results
Copy the generated CSS border-radius code from the output panel and paste it into your stylesheet to apply the shape to any element.
Real-world examples
Organic Blob Avatar
Input: Corners around 55%, 45%, 60%, 40%.
Results: A soft, asymmetric blob that crops a square image into a modern organic avatar.
Use case: Frontend developers create playful profile shapes without image editing.
Leaf Or Petal Shape
Input: Opposite corners high (near 100%) and the others low.
Results: A pointed leaf-like silhouette perfect for badges and decorative icons.
Use case: Designers add natural, botanical flourishes to cards and illustrations.
Speech Bubble Panel
Input: One corner near 0% with generous rounding elsewhere.
Results: A bubble-style panel with one sharp corner anchoring the tail direction.
Use case: Bloggers shape comment threads and chat widgets visually.
Hero Section Art
Input: Extreme mixed percentages for dramatic contrast between corners.
Results: A striking abstract container shape for hero imagery.
Use case: Landing pages gain distinctive geometry without SVG masks.
Soft Card Variant
Input: All sliders set to gentle values close to one another.
Results: A subtly irregular rounded card that feels hand-drawn rather than mechanical.
Use case: Designers soften grid layouts with slightly imperfect card corners.
Border Radius Generator FAQ
Is an account required to use this tool?
No, you can use this tool instantly without registering or logging in.
Is my data secure and private?
Yes, all processing happens directly in your browser, meaning your design data is never sent to our servers.
Does the tool work offline?
Once the page is loaded, the core generation engine works entirely offline in your browser.
Why percentages instead of pixels?
Percentage-based radii scale fluidly with element size, so one generated rule keeps its shape on any screen or container.
What does the slash in the output mean?
Border-radius accepts eight values split by a slash: horizontal radii before it and vertical radii after it, which enables organic elliptical shapes.
What is the technical working principle?
The tool maps your slider inputs to the CSS border-radius shorthand syntax and applies them to a DOM element.
What is the most common use case?
Developers most commonly use it to quickly design organic blobs, leaves, and custom UI shapes without memorizing CSS shorthand.
Why use the Border Radius Generator?
- Visual Shape Building: See the exact shape of your element as you adjust the corner values.
- Shorthand Automation: Automatically generates the correct CSS shorthand syntax for all four corners.
- Complex Shapes Made Easy: Easily create asymmetrical shapes and custom UI elements.
- Cross Browser Compatible: Generates standard CSS that works perfectly across all modern browsers.
- Browser based Privacy: Keeps your design concepts secure by processing everything locally.
- Zero Setup Required: Works immediately in any modern web browser without installations.
- Completely Free: Offers full functionality without hidden paywalls or premium tiers.
- Clean Code Output: Generates properly formatted CSS ready to be pasted into your project.
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