What is the formula for calculating true heading from magnetic heading?

The formula for calculating true heading from magnetic heading involves understanding the relationship between the magnetic and geographic (true) north. True heading is derived from magnetic heading by accounting for magnetic variation, which is the difference between magnetic north and true north at a given location.

When you use magnetic heading, you are referencing the direction towards magnetic north. To convert this to true heading, you need to apply magnetic variation (also referred to as magnetic declination). If magnetic variation is east, you would add it to the magnetic heading. If magnetic variation is west, you would subtract it.

Therefore, the formula True Heading = Magnetic Heading + Magnetic Variation accurately reflects this relationship, allowing pilots to navigate accurately with respect to the Earth’s geographical features.