Enter the Magnetic Azimuth and Magnetic Variation or Declination into the calculator to determine the Grid Azimuth. This calculator can also evaluate any of the variables given the others are known.

Magnetic Azimuth To Grid Azimuth Formula

The following formula is used to calculate the Grid Azimuth from the Magnetic Azimuth.

GA = MA + V

Variables:

  • GA is the Grid Azimuth (degrees)
  • MA is the Magnetic Azimuth (degrees)
  • V is the Magnetic Variation or Declination (degrees)

To calculate the Grid Azimuth, add the Magnetic Azimuth to the Magnetic Variation or Declination. The Magnetic Variation is the angle between magnetic north and true north and can be either east or west. If the Magnetic Variation is west, it should be subtracted from the Magnetic Azimuth. If it is east, it should be added to the Magnetic Azimuth.

What is a Magnetic Azimuth To Grid Azimuth?

Magnetic Azimuth to Grid Azimuth is a conversion process used in navigation and mapping to align the magnetic north, which is the direction a compass points, with the grid north, which is the vertical lines on a map. This is necessary because the Earth’s magnetic north and the grid north on maps do not always align perfectly due to the Earth’s magnetic field variations. The difference between the two is known as magnetic declination or variation, and it is used to convert magnetic azimuths to grid azimuths and vice versa.

How to Calculate Magnetic Azimuth To Grid Azimuth?

The following steps outline how to calculate the Magnetic Azimuth To Grid Azimuth.


  1. First, determine the Magnetic Azimuth (MA) in degrees.
  2. Next, determine the Magnetic Variation or Declination (V) in degrees.
  3. Add the Magnetic Azimuth (MA) and the Magnetic Variation or Declination (V) together.
  4. Finally, you have calculated the Grid Azimuth (GA) in degrees.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Magnetic Azimuth (MA) = 120 degrees

Magnetic Variation or Declination (V) = 10 degrees