4A

4A or IV-A may refer to :


 * 4A, Ararat International Airlines' IATA airline designator
 * 4A, a series of Toyota A engine produced by Toyota Motor Corporation (1982-2002)
 * 4A, the production code for the 1974–75 Doctor Who serial Robot
 * 4A Centre for Contemporary Asian Art, Sydney, Australia
 * 4A Engine, a video game engine developed by 4A Games
 * 4A Games, a video game development company in Ukraine
 * Calabarzon or Region IV-A, a Region in the Philippines
 * Pixel 4a, an Android smartphone
 * Vermont Route 4A, a highway in Vermont, U.S.
 * Zeolite 4A, a sodium-type molecular sieve