Field magnet refers to a magnet used to produce a magnetic field in a device. It may be a permanent magnet or an electromagnet. When the field magnet is an electromagnet, it is referred to as a field coil.

Although the term usually refers to magnets used in motors and generators, it may refer to magnets used in any of the following devices:

• Alternator
• Cathode ray tube
• Dynamo
• Electric motor
• Electrical generator
• Fusion reactor
• Loudspeaker
• Maglev trains
• Magnetic Separator
• Magneto
• Mass spectrometer
• Metal detector
• MRI scanner
• Particle accelerator
• Read/write head
• Relay
• Solenoid
• Stepping switch
• Tape head