Free geometry tool
Circle Calculator
Calculate circle area, diameter, circumference, and radius.
Side a
3 m
Side b
4 m
Side c
5 m
Area
6 m^2
Perimeter
12 m
Browser-based processing is used where supported. Review each tool's privacy notes before entering sensitive information.
About Circle Calculator
Calculate circle area, diameter, circumference, and radius. This tool runs in your browser.
How to use it
- Enter your values.
- Review the result.
- Clear the fields to start again.
Key Features
- ✓ Browser-based processing
- ✓ Instant results
- ✓ No server upload
Frequently Asked Questions
Is my data uploaded?
No. Calculations happen locally in your browser.
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