The piezo-resistive coefficient π44 is reported for the case of single crystalline p-type silicon. By comparing the measured sensitivity of pressure sensors with the simulated sensitivity of these pressure sensors, we are able to extract π44 since this is the only free parameter in the simulation. A value of π44 = (108.3 ± 2.1) × 10−11 Pa−1 at a dopant concentration of (5.0 ± 4.5) × 1017 cm−3 was found, which is in good agreement with experimental literature data