Developer Utilities · Free tool
Border Radius Generator
Create organic CSS border-radius with independent corner controls instantly online. Generate the exact rule or full 8-value shorthand free in your browser.
Updated June 2026
CSS
border-radius: 16px;
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What it does
Design CSS border-radius with four independent corner controls and live preview. Copy the short form (8px), per-corner (8px 16px 8px 16px), or full 8-value elliptical form — exactly the CSS you'll paste.
Pair with box shadow generator, gradient generator, and CSS clamp generator.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/border-radius-generator" width="100%" height="720" frameborder="0" loading="lazy" title="Border Radius Generator" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Drag the corner sliders to shape the rectangle.
- Toggle unified vs per-corner modes.
- Switch between px, %, and em units.
- Copy the CSS rule.
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Learn more
Guides about this topic
- Design & Media · GuideHow to choose border radius valuesDetermine perfect border radii with design-system scales and the nested-radius formula. Free, online guide for shaping buttons, cards, and squircles.
- How-To & Life · GuideHow to Use border-radius in CSSShorthand vs individual corners, percent vs pixel values, elliptical radii, and common patterns (pill, card, avatar).
- Using Our Tools · GuideHow to generate QR codesMake QR codes for URLs, WiFi, vCard, or text. Learn error correction and sizing, then generate your QR code online free with no sign-up in seconds.
- Using Our Tools · GuideHow to create a strong passwordGenerate a strong password instantly online for free. Build high-entropy passphrases following NIST 2026 rules with no download needed.
- Developers & Technical · GuideHow to encode and decode Base64Understand the 3-to-4 mechanic and 33% overhead for standard, URL-safe, and MIME Base64. Free online reference to avoid common mistakes, no download needed.
- Design & Media · GuideHow to choose a color paletteBuild accessible color palettes using HSL theory, monochromatic to triadic schemes, WCAG contrast checks, and dark mode tips. Free, no-download guide.
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