Heat flux gauges are widely used directly or to calibrate camera imaging system in order to determine the flux density and incident power of concentrated solar plants. Several laboratories have developed techniques to calibrate these sensors but with varying procedures and apparatus. No recent work has been conducted to check the degree of agreement between the calibrations from different laboratories for solar applications [1] [2].This paper describes the results of the comparison of 4 sensors: 3 Gardon heat flux gauges and a water calorimeter were compared at the Big Solar Furnace in Odeillo for varying heat flux density and incoming angles up to 1500kW/m2 and 25 to 80°. Two Vatell commercial gauges had been calibrated with an electric heated radiative plate. One of them had been further corrected for the spectral distribution difference between the radiative plate (mostly infrared) and concentrated solar applications (mostly visible) [3]. One HyCal commercial gauge had been calibrated against a Kendall water-cooled absolute radiometer. The water calorimeter was representing cavity absolute radiometers exhibiting total apparent absorptivity.We have observed an agreement within 10% of all the sensors, but with a separation in two subgroups: on one hand the radiative plate calibrated gauges agreeing each around 1%, solar corrected or not, and on another hand the radiometer calibrated gauge and the water calorimeter. Additional experimental findings concerning angular response are also presented