ampere/inch [A/in] Unit Converter

Definition of ampere/inch [A/in] unit

Ampere per inch (A/in) is a unit of linear current density, quantifying electric current distributed across each inch of width. It denotes one ampere of current for every inch and equals approximately 39.37 amperes per meter.

History of ampere/inch [A/in] unit

The ampere per inch developed from traditional engineering practice of describing sheet currents and magnetizing forces by width rather than area. It became especially familiar in electromagnetic design, where current sheets on conductors, coils, and magnetic cores were conveniently specified in amperes per unit length. The SI system later standardized the ampere per meter (A/m) as the corresponding linear current-density unit, while ampere per inch remained common in older technical literature, American engineering documents, and commercial specifications. Its meaning is unchanged: a width-based measure of current distribution.

Applications of ampere/inch [A/in] unit

Today, ampere per inch appears mainly in legacy engineering documentation, electromagnetic calculations, and specifications for coils, busbars, and conductive sheets. It can describe surface current on a foil, winding current distributed across a core face, or magnetomotive force per inch in magnetic circuits. Modern work usually converts it to A/m; 1 A/in equals 39.37 A/m.

Complete list of ampere/inch [A/in] unit conversion