NdFeB composition defines the elemental structure of neodymium-iron-boron magnets, which are among the most widely used high-performance permanent magnets. These materials are mainly composed of neodymium (Nd), iron (Fe), and boron (B), forming the Nd₂Fe₁₄B crystal phase that determines their strong magnetic behavior. Neodymium contributes magnetic anisotropy, enabling high coercivity and magnetic stability. Iron provides high magnetic saturation, which supports strong magnetic output. Boron stabilizes the crystal lattice, ensuring consistent material performance. In industrial production, additional elements such as dysprosium or terbium may be introduced to improve thermal stability and resistance to demagnetization. Because of their high magnetic energy density and compact size, NdFeB magnets are widely applied in electric motors, renewable energy systems, automation equipment, and electronic devices. A clear understanding of NdFeB composition supports proper material selection, performance optimization, and reliable operation across various technical applications.