The north and south poles of a magnet are equally strong. The strength of a magnet refers to the ability of the magnet to produce a magnetic field and to attract or repel other magnets or magnetic materials. A magnet's strength is independent of its magnetic pole.
In general, the strength of a magnet is determined by its material and the shape of its magnetic field. The magnetic field is the area around the magnet in which the magnetic force is present. The shape of the magnetic field can affect the strength of the magnet, as can the size and shape of the magnet itself.