Low carbon steel wire is also known as iron wire. Low carbon steel wire is a kind of metal wire made of low carbon steel. The composition of iron wire varies according to different uses. The ingredients it contains are: iron, cobalt, nickel, copper, carbon, zinc, and other elements. The carbon content of low carbon bright alkaline steel wire ranges from 0.06 to 0.20 percent, but the most commonly used grades are 1008 (0.08 percent carbon) and 1018 (0.18 percent carbon). Low-carbon bright alkaline steel wire is most often supplied in a "drawn" or "hard drawn" state, but can also be supplied in a bright annealed state according to special requirements.

High carbon steel is used to make spring tempered carbon steel wire. Commonly used grades of spring steel wire do not have a specific chemical name. They are instead specified and manufactured according to performance criteria specific to their primary end use, which is the manufacture of coil springs.