Click Ruler  or Square Ruler , position the cursor where you want to start the measurement, hold down the mouse button, and drag the cursor to the point where you want to end the measurement.

You can change the unit of measure in your Smart Review preferences.

Note: If you make a measurement while in a group review session, other users in the session cannot see the measurement.

Perform one of the following actions:

• Right-click (Ctrl+click on a Mac computer) the measurement and select Delete.
• In the Annotations panel, right-click the measurement that you want to delete, and select Delete.

Note: 
Measurements are not saved across sessions or included in reports.
Measurements are removed automatically when you change the file that is open in Smart Review or quit the Smart Review session.