| Ordinary magnet | Coded magnet | |
|---|---|---|
| Poles on the face | One north, one south | Many, in a designed pattern |
| Reach | Long — falls off slowly | Short — poles cancel with distance |
| Holding force on contact | High | Can be high; depends on the pattern |
| Behaviour | Sticks | Attach, align, latch, detent, spring, shear, torque, release |
| Collects swarf and debris | Yes, readily | Much less |
| Near electronics or cards | Risky | Comparatively safe at short distance |
| Cost per part | Lower | Higher — the pattern has to be written |
| Best when | You need pull, cheaply, and reach is fine | You need a defined behaviour, or you need the field to stay local |
The short version. If the job is “hold this up” and nothing
nearby minds a magnetic field, an ordinary magnet is cheaper and probably better. If the job has
a verb in it — align, latch, click, release, resist sliding — or the field has to
stay put, that is where coded earns its cost.
The material question is separate
Both come in neodymium, ferrite, samarium cobalt and alnico. That choice is about strength, temperature and corrosion, and it is made independently of whether the part is coded.