A brushless motor includes a rotor and a stator. The rotor is provided with a rotor core including a plurality of magnet poles and a plurality of core poles. A void is formed at a boundary between each core pole and an adjacent magnet pole in the circumferential direction. Each magnet pole includes a peripheral core portion located closer to the stator than the magnet in the radial direction of the rotor. The void formed in at least one of two circumferential sides of each magnet pole includes an extended void region that extends into the peripheral core portion toward a middle point of the magnet pole in the circumferential direction.