The border radius generator works like this: it shapes rounded corners visually with per-corner control and outputs the shorthand CSS, including elliptical radii. Everything happens on your device - the input never leaves your tab unless the tool clearly states it performs a server-side lookup.
How to use the Border Radius Generator
Paste the input (code, data or query).
Run the operation - formatting and validation are instant.
Read any validation message before trusting the output.
Copy the result into your project.
Features
Instant client-side formatting and validation
No telemetry on your data
Copy-ready output with proper escaping
Common mistakes to avoid
Using the wrong input dialect (JSON vs JSON5, cron 5 vs 6 fields)
Copying output without checking escaping
Examples
Input
Result
Corners 8/8/24/24
border-radius: 8px 8px 24px 24px;
Best used for
Getting a reliable answer for border radius generator without installing an app
One-off tasks done in under a minute from any device
Checking results before committing them to something important
Working on a phone where desktop software is unavailable
Privacy
All parsing and transformation happens locally in this tab - your code and data are not sent anywhere.
Frequently asked questions
Can I make pill shapes?
Set all corners to half the element's height (or 999px) for a full pill.
How do elliptical corners work?
Separate horizontal and vertical radii (the slash syntax, like 30px / 60px) turn each corner into a quarter-ellipse - the visual editor drags both independently.
What is the shorthand rule emitted?
Up to four values clockwise from top-left, collapsing automatically - one value rounds all corners equally, and the generator always emits the shortest correct form.