How to Calculate a Reverse Direction

Because the system of degrees used to measure direction is marked as a regular set of points around a circle, you can calculate the opposite of any direction on a compass.

Instructions

Difficulty: Easy

Things You’ll Need:

• Notebook Papers And Pencil
• Base Plate Compasses

1. Add 180 degrees to calculate the reverse direction if the original direction is between 0 and 180 degrees.
2. Subtract 180 degrees to calculate the reverse direction if the original direction is between 180 and 360 degrees.
3. Set the baseplate compass to the reverse direction to return to your starting point.

Tips & Warnings

• If you carefully record all the directions you travel, and note each place you change direction, you can retrace your route using reverse directions.
• Double-check your arithmetic before you begin the return journey.
• Reverse directions are also called back azimuths, back bearings, reciprocal bearings, reciprocal directions or reciprocal headings.