# Radius, diameter, & circumference

Practice finding the radius, diameter, or circumference of a circle. For example, if the diameter of a circle is 16, what is its circumference?

If you're seeing this message, it means we're having trouble loading external resources for Khan Academy.

If you're behind a web filter, please make sure that the domains ***.kastatic.org** and ***.kasandbox.org** are unblocked.