The Chorasmian era was a calendar era (year numbering) used in Chorasmia (Khwarazm) between the 1st and 8th centuries AD.
The epoch (first year) of the era is not known precisely, but fell between 42 BC and AD 20.[1] It probably marked the independence of Chorasmia from the Parthian Empire and the establishment of a native dynasty. It was probably the official calendar. It was in use for at least 738 years, since that is the latest dating found using the era.[2]
The Chorasmians used a variant of the Zoroastrian calendar with Chorasmian names for the months and days.[3]