Neutral points

When two fields overlap, they add as vectors. This is called superposition. Where two fields are equal in size and opposite in direction, the total is zero. That spot is a neutral point (or null point).

A compass at a neutral point feels no field, so it has no preferred direction. It stays wherever you leave it.

A single magnet can make neutral points too, together with Earth's field. Wherever the magnet's field is exactly 50 µT and points south, it cancels Earth's northward field.

For a magnet lying with its N end pointing south, those spots are on its axis, one beyond each end. Turn the magnet so its N end points north, and the neutral points move to either side of its middle, to the east and west.