HDT may refer to:
HDT (data format), a data compression format Hardware Detection Tool, software for SYSLINUX Hawaii–Aleutian Daylight Time Heat deflection temperature, at which a polymer deforms under load Holden Dealer Team, a former car-racing team Henry David Thoreau, American transcendentalist poet Heavy Duty Truck (HDT), a class 7 or 8 prime mover, the term is usually used in the fifth wheel rv industry