OM1 fiber optic cable is the optical fiber cable with traditional 62.5/125 multimode fiber. The OM1 fiber was first developed by Bell laboratory in the early 1980s. OM1 standard is defined by ISO/IEC 11801 in 2002; related standards are OM2, OM3 which are for multimode and OS1 which is for single mode.

OM1 cable optical fiber is bigger core diameter; it makes the OM1 fiber better ability on concentrating the light and bend-resistance. OM1 fiber optic cables are widely used especially before the mid 1990s and it became a standard multimode fiber in the U.S.A. OM1 fiber was the indoor cabling standard chosen by AT&T, ANSI and IBM. For OM1 fiber cable, the max attenuation is 3.5Db/km working at 850nm, 1.5dB/km at 1300nm. Overfilled launch of OM1 fiber optic cable at 850nm is 200MHz*km, at 1300nm is 500MHz*km. Today, OM1 fiber optic cables are still a popular indoor use multimode fiber optic cable.