Arc Length

Selection prerequisites: One or more arcs, or a circle and two or three points on the circle.

If one or more arcs are selected, this command measures the length of each selected arc, using the distance units chosen on the Units panel of the Preferences dialog box. If a circle and two points are selected, this command measures the length of the minor arc on the circle defined by the two selected endpoints. If a circle and three points are selected, this command measures the length of the minor or major arc on the circle that starts at the first selected point, passes through the second, and ends at the third.

See also
Units Preferences
Circles and Arcs
Angle
Arc Angle
Selecting and Deselecting Objects
Measurements