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Magnetic Variation Calculation:
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Magnetic variation (also known as magnetic declination) is the angle between true north and magnetic north. This difference occurs because the Earth's magnetic north pole and geographic north pole are not located at the same point.
The calculator uses the magnetic variation formula:
Where:
Explanation: A positive result indicates east variation, meaning magnetic north is east of true north. A negative result indicates west variation, meaning magnetic north is west of true north.
Details: Accurate magnetic variation calculation is crucial for navigation, aviation, marine operations, and surveying. It ensures proper alignment between compass readings and true geographic directions.
Tips: Enter both true heading and magnetic heading in degrees (values between 0-360). The calculator will compute the variation and display whether it's east or west variation.
Q1: What's the difference between magnetic variation and magnetic deviation?
A: Variation is the difference between true north and magnetic north. Deviation is the error caused by local magnetic fields on a compass.
Q2: Does magnetic variation change over time?
A: Yes, magnetic variation changes gradually over years due to shifts in the Earth's magnetic field. Navigation charts are regularly updated with current variation values.
Q3: How does magnetic variation affect navigation?
A: Pilots and navigators must apply variation correction to convert between magnetic headings (what the compass shows) and true headings (actual direction relative to Earth's axis).
Q4: Is magnetic variation the same everywhere?
A: No, magnetic variation differs by geographic location. It can range from 0° to over 20° east or west depending on where you are on Earth.
Q5: How often should variation values be updated?
A: For precise navigation, variation values should be checked against current aeronautical or nautical charts, as the magnetic field changes over time.