T81

T81 may refer to:
 * T.81 (ITU-T recommendation), a JPEG image standard
 * Cooper T81, a racing car
 * Hawker Hunter T.81, a British-built trainer aircraft
 * T81 Chemical Mortar Motor Carriage, an American chemical weapons delivery system
 * Tatra 81, a Czechoslovak heavy truck
 * Type 81 assault rifle