Circle calculator
Calculate a circle's diameter, circumference and area from its radius.
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Circle calculator — workspace
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How to use: Circle calculator
Start with the example, or replace it with your own values.
Review Radius, then select “Get result”.
Read the result, then copy or download it. Edit any input to try again.
What you can do
- Calculate a circle's diameter, circumference and area from its radius.
What you get
- A result you can review, copy or download. Numeric tools show labeled calculations; text tools show the transformed output.
What you need
- Radius
- Enter a number (0–1000000).
Try an example
- Radius
5
Good to know
- Use a current browser with JavaScript enabled. Available formats and speed depend on your browser, device and input size.
Your work stays on your device
Your files and entered values are processed in your browser and are not uploaded for processing. The website and any required processing engines still download from the site.
Questions & answers
Is Circle calculator free?
Yes. Circle calculator is free to use and does not require an account.
Are my files or entered values uploaded?
Your files and entered values are processed in your browser and are not uploaded for processing. The website and any required processing engines still download from the site.
What result can I save?
A result you can review, copy or download. Numeric tools show labeled calculations; text tools show the transformed output.
What should I check before using the result?
Use a current browser with JavaScript enabled. Available formats and speed depend on your browser, device and input size.