8400

8400 or variation, may refer to:

In general

 * A.D. 8400, a year in the 9th millennium CE
 * 8400 BCE, a year in the 9th millennium BC
 * 8400, a number in the 8000 (number) range

Other uses

 * 8400 Tomizo, an asteroid in the Asteroid Belt, the 8400th asteroid registered
 * Texas Instruments 8400 series ICs, a variant of the 7400-series integrated circuits
 * Kintetsu 8400 series electric multiple unit train series