Measure Geometry Radius
Measure Geometry Radius measures and reports the radius of a circle, circular arc or Bezier curve.
Select Home > Measurement > Geometry Radius:
Click the required curve item on the screen.
An Information box shows the radius in the units and number of decimal places as set in the Coordinate Reference Systems dialog.
To change the units or number of decimal places, see Home > Map > CRS > Units.
Click the Copy to clipboard button to copy the values to the Windows clipboard as text.
When pasted back, the values are placed as a text item at the centre of the current map window. They can also be pasted into a text dialog box or a spreadsheet.
Click the x button in the Information box to dismiss the message.