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Measure a Bearing


A protractor or compass can be used to measure a map bearing; a protractor is easier to use and more accurate than a compass. There are different types of protractors, but a common one is made out of flat clear plastic and is in the shape of a semi-circle with degree marks.




Using a Protractor to Measure a Bearing on a Map

Steps to measure a bearing on a map using a protractor

  1. Center the protractor over the starting point and orient 0° with true north (the 0° line needs to be parallel with the edge of the map).
  2. Draw a line on the map from the starting point towards the destination. If you don't want to draw a line of your map, align a string or ruler with the start point and destination point.
  3. Read the bearing where the line, string or ruler intersects the protractor. This is the direction of travel to your destination.
  4. Before using this bearing in the field, adjust the compass for declination.

Measuring a bearing with a protractor

Using a Compass to Measure a Bearing on a Map

Steps to measuring a magnetic bearing on a map using a compass

  1. Adjust the compass for map declination. Disregard the magnetic needle.
  2. Place the compass on the map, where one edge of the base plate touches both the start point and destination point. The direction-of-travel arrow needs to point toward the direction of the destination.
  3. Turn the compass housing so that the orienting arrow points to true north, parallel to map edge and longitude lines.
  4. Read bearing at the index line. This is the direction in degrees of the magnetic bearing.

Measuring a bearing with a compass where the edge of the base plate touches both the start point

Note: To find a true bearing using a compass, follow the same steps, but set the declination on the compass at 0°

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