Neodymium magnets are made in two broad ways, and the choice changes strength, shape freedom, tolerance and cost. It is worth settling early, because the two routes lead to genuinely different parts.
Sintered: maximum strength in minimum volume
Sintered magnets are pressed from powder, sintered, and then cut and ground to size. They deliver the highest magnetic strength for a given volume, which is why they dominate motors and demanding holding applications. The trade-off is shape: they are brittle, and anything beyond simple blocks, discs, rings and arcs becomes a grinding job that adds cost.
Bonded: shape freedom and consistency
Bonded magnets mix magnetic powder with a polymer binder and are moulded close to final shape. That allows thin walls, complex geometry and consistent dimensions in large quantities without extensive grinding, and they are less brittle. The price is magnetic strength, which is only a fraction of what a sintered magnet of the same volume provides, and the binder can limit the usable temperature for some types.
A simple way to decide
If the job is to produce as much force or field as possible from the smallest space, sintered is usually the answer. If the part has a complicated shape, a very thin wall, or must be made in high volume with tight consistency, bonded deserves a serious look. Tell us what the magnet has to do, not only what shape you think it should be, and we will suggest the route before any tooling is committed.