How to Use a Compass: A Beginner's Guide

A compass is the simplest navigation tool there is: a magnetised needle that turns to point north, wherever you are. Knowing which way is north turns a strange street, a trail or a field into something you can find your way through. Here is how to read one.

How does a compass work?

The Earth behaves like a giant, weak magnet. A compass needle is a small magnet balanced on a pivot so it can turn freely, and it lines itself up with the Earth's magnetic field — one end pointing towards magnetic north. On almost every compass that end is painted red or marked N.

The parts of a compass

• The needle — the red (or marked) end points north.
• The dial, or compass rose — the directions N, E, S and W, often with the points in between and degree markings from 0 to 360.
• The housing — the case that holds it all and keeps the needle level.

How to read a compass

1. Hold it flat and level in your palm, at about waist height. A tilted compass lets the needle drag.
2. Keep still and wait a moment for the needle to settle.
3. Turn the compass, not the needle, until the N on the dial sits under the red end of the needle.
4. Now the dial is aligned. Every direction on it points the right way: east is to your right, south behind you, west to your left.

How to use a compass without a map

To head in a particular direction:

1. Align the compass as above.
2. Find the direction you want on the dial — say, north-east.
3. Look along that line and pick a landmark directly ahead: a tree, a tower, a corner.
4. Put the compass away and walk to the landmark, then repeat.

Walking from landmark to landmark keeps you straight; staring at the needle while you walk does not.

To retrace your steps, the way back is simply the opposite direction: if you walked north-east, return south-west.

Magnetic north and true north

A compass points to magnetic north, which is not quite the same as the North Pole (true north). The difference, called declination, depends on where you are — across the United States it ranges from almost nothing to more than ten degrees. For finding your bearings it rarely matters; for serious navigation with a map, you correct for it using the declination printed on the map.

Mistakes that throw a compass off

• Metal and magnets nearby. Phones, car bodies, steel railings, belt buckles and other magnets pull the needle. Step away from them before you take a reading.
• Holding it tilted. The needle catches on the housing.
• Following the needle instead of the landmark. You drift without knowing it.
• Storing it next to a magnet, which can weaken the needle over time.

A pocket compass for the desk or the trail

A pocket compass with a hinged cover is part instrument, part keepsake — the traveller's companion to a pocket watch. It is perfect for finding your bearings on a walk or in a new city. For real backcountry navigation, carry a proper baseplate compass and a map, and learn to use them together before you need to.