A coded magnet is a permanent magnet whose face carries a designed pattern of many small north and south regions, instead of one north face and one south face. The pattern is the code. Two magnets printed with matching codes interact strongly with each other, and the pattern decides how the pair behaves as it approaches, touches or turns.
That matters to an engineer because a conventional magnet's behavior is set almost entirely by its size, shape and grade. A coded magnet's behavior is also set by its pattern. The same blank can be patterned to hold harder at contact, pull itself into alignment, push away until it passes a set point and then latch, or click between rotational positions.
The category traces to Correlated Magnetics Research (CMR) of Huntsville, Alabama, which sells coded magnets under the Polymagnet name. CMR's history page says its co-founder borrowed patterns, or codes, from signal processing theory to arrange magnetic fields. CMR describes Polymagnets as programmable magnets, and its catalog sorts them by behavior: attach, align, latch, spring and torque.
You will also see the terms programmable magnet, correlated magnet and smart magnet used for the same idea. Multipole magnet is a broader term that also covers simple alternating-pole rings.
WholeMagnetics, 2026-10-04. Polymagnet facts are taken from Correlated Magnetics Research’s public pages, listed below; vendor performance figures are CMR’s own.