AC-4 or AC4 may refer to:

Music AC4 (band), a Swedish hardcore punk band, or their eponymous album

Vehicles Aircraft Light Wing AC4, an aircraft Aviastroitel AC-4 Russia, glider Comte AC-4, a two-seat Swiss monoplane

Ships , a US Navy collier ship

Trains Southern Pacific class AC-4, a class of steam locomotive

Tanks AC4 tank, a World War Two Australian cruiser tank

Technology AC-4, an IEC Utilization Category Dolby AC-4, Dolby Digital audio codec

Videogames Ace Combat 04: Shattered Skies, a 2001 video game Armored Core 4, a 2006 video game Assassin's Creed IV: Black Flag, a 2013 video game

See also

AC (disambiguation)