Border Radius Generator · Free CSS Rounded Corners Tool 2026
Create custom border-radius values for each corner individually. See live preview and copy CSS code. Perfect for buttons, cards, images, and UI elements. 100% free.
customizable
How it works: Adjust each corner's radius independently or link them together. Change preview size and color to match your design. Copy the CSS code for your elements.
🎯 Why Use a Border Radius Generator?
Border-radius is one of the most frequently used CSS properties for modern UI design. It softens sharp corners on buttons, cards, images, modal windows, and containers, creating a friendlier, more polished look. However, writing `border-radius` with four values (top‑left, top‑right, bottom‑right, bottom‑left) can be confusing, especially when you want different values for each corner. Our Border Radius Generator gives you individual sliders for each corner, a live preview, and the ability to link all corners together for uniform rounding. You can also adjust the preview box size and background color to simulate your actual design. The generated CSS code is clean and ready to copy into your stylesheet. This tool is perfect for front‑end developers, UI designers, and anyone who wants pixel‑perfect rounded corners without trial‑and‑error.
All processing is client‑side – your settings stay private. The tool includes a reset button that sets a classic "pill" shape (50% for all corners if width/height are equal? Actually reset sets 50px for all corners for demonstration). The usage counter and star rating are stored in localStorage. Best of all, it's 100% free with no signup or watermarks.
📘 How to Use the Border Radius Generator
- Adjust individual corners – Use the sliders for top‑left, top‑right, bottom‑right, and bottom‑left (0–100px).
- Link corners (optional) – Check "Link corners (all same)" to make all corners follow the top‑left value.
- Customize preview size – Change width and height to match the element you're styling (e.g., button vs card).
- Pick a background color – See how rounded corners look with your brand color.
- Copy CSS – Click "Copy CSS" to get the `border-radius` declaration.
- Reset to pill shape – Click reset to set a large uniform radius (50px) to create a pill/button shape.
✨ Powerful Features
⚙️ How the Border Radius Generator Works Under the Hood
We maintain separate values for each corner (tl, tr, br, bl). When the "Link corners" checkbox is checked, all sliders except top‑left are disabled and visually hidden? Actually we update them programmatically: if linked, when top‑left changes, we set the other three to the same value and update their displays. The live preview element's `border-radius` CSS property is set to the four values in clockwise order: `tl px tr px br px bl px`. The CSS output textarea shows the exact property. The copy button uses the Clipboard API. The reset button sets a uniform 50px radius (pill shape) and links corners. The preview size and color are applied via inline styles. The tool also increments a usage counter and supports star rating and like/dislike feedback, all stored in localStorage. All operations are client‑side and extremely fast.
🌟 Benefits for Web Design
Pixel perfect: Fine‑tune each corner to match mockups. Rapid prototyping: Test different rounding styles in seconds. Educational: Understand how the four‑value syntax works. Consistency: Generate reusable CSS for your UI components. Free forever: No hidden costs. Plus, the integrated rating and share buttons help you support the tool.
❓ Frequently Asked Questions (FAQ)
1. What is the border-radius syntax?
`border-radius: top-left top-right bottom-right bottom-left;`. If one value is given, all corners are set to that value. Two values: first = top-left & bottom-right, second = top-right & bottom-left. Our generator outputs four values for maximum control.
2. How do I create a circle or pill shape?
For a pill shape (rounded ends), set the border-radius to half of the height for a rectangle, or 50% for a perfect circle (square width/height). Use our reset button to see a pill example.
3. Does border-radius work on images?
Yes, apply it to `` or a container div. Our preview box simulates any element.
4. Can I use percentage values?
Our tool uses pixels for simplicity. Percentages are relative to the element's dimensions. After copying, you can change `px` to `%` if needed.
5. Does it support different values for each corner?
Yes, that's the main feature. The CSS output will have four numbers.
6. How do I use the generated CSS?
Copy the `border-radius` line and paste it into your stylesheet for the desired element (e.g., `.button { border-radius: 10px 20px 30px 40px; }`).
7. Can I export multiple radius styles?
You can copy one style at a time. Use the sliders to create different presets and copy each separately.
8. How can I help improve this tool?
Use the star rating, like/dislike buttons, and share the tool with fellow developers.
🔗 Related CSS Design Tools
💡 Pro tip: For card components, use 8‑16px radius. For large banners, use 20‑30px. For pill‑shaped buttons, set radius to half the height (e.g., height 48px, radius 24px).