A compact 60 GHz class-J/F amplifier in 22 nm FDSOI (fully depleted silicon on insulator) CMOS with high efficiencies at low supply voltages is analyzed and presented in this paper. It utilizes a pseudo-differential common source gain cell with a 0.8 dB insertion loss output transformer balun. At 1.1 V, 0.6 V, and 0.4 V supply, power added efficiencies of 42.3 %, 37.7% and 29.8%, and saturated output powers of 14.3 dBm, 9.5 dBm and 6.4 dBm, respectively, are measured. The active circuit area is only 0.0198 mm2.