Like the rest of the A class, "Active" had a main gun armament of four guns on low angle (30 degree) mounts that were only suitable for anti-ship use, and an anti-aircraft armament of two 2-pounder (40 mm) "pom-poms". Eight torpedo tubes were carried on two quadruple mounts, with Mark V torpedoes carried. No sonar set was initially fitted, although provision was made to fit one later, while anti-submarine armament consisted of three depth charge chutes with six depth charges carried. High speed minesweeping equipment was also fitted.