Geometry
Circle Diameter
Diameter from radius.
Formula
Formula
d = 2 r
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| r | radius | real number (ℝ) | — | input |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenradius r = 5
Result10
Example 2
Givenradius r = 7.5
Result15