A11
A11, A 11 or A-11 may refer to:
Military
- Aero A.11, a Czechoslovakian bomber produced before World War II
 - Consolidated A-11, an attack version of the Consolidated P-30 fighter plane of the 1930s
 - HMS A11, an A-class submarine of the Royal Navy
 - Matilda Mk I, a British Army infantry tank
 - Aggregate 11, a proposed military rocket of Nazi Germany
 - A-11 Ghibli, the Italian designation for the AMX International AMX
 
Other uses
- A11 road, in several countries
 - Apollo 11
 - A-11 offense, an American Football shotgun formation involving 2 quarterbacks and 9 other potentially eligible receivers
 - Arrows A11, a 1989 British racing car
 - ATC code A11 Vitamins, a subgroup of the Anatomical Therapeutic Chemical Classification System
 - British NVC community A11 (Potamogeton pectinatus - Myriophyllum spicatum community), a British Isles plant community
 - Chery A11, a 1999 Chinese car
 - HLA-A11, an HLA-A serotype
 - American Airlines Flight 11, a plane that was hijacked and crashed into the World Trade Center in the September 11 attacks
 - English Opening, Encyclopaedia of Chess Openings code
 - Apple A11, an ARM SoC mobile processor designed by Apple
 - Samsung Galaxy A11, an Android device developed by Samsung Electronics
 - "A-11", a 1963 country song written by Hank Cochran