Three-Point Radius Measurement

The Three-Point Radius measurement tool places specialized markups that calculate the radius as an arc. While a markup placed with the Three-Point Radius tool can be made into a full circle after it has been placed, it always starts as an arc; to place a circular markup that also calculates the radius of the circle, see Center Radius Measurement.

Before placing a measurement, it is recommended that you calibrate the page scale for the document first. When trying to place a measurement on a page that does not have a page scale, you will be prompted to set the scale.