Measurements leading to the calculation of the standard thermodynamic properties for gaseous diphenylmethane (Chemical Abstracts registry number [101-81-51) are reported. Experimental methods include adiabatic heat-capacity calorimetry, vibrating-tube densimetry, comparative ebulliometry, inclinedpiston gauge manometry, and differential-scanning calorimetry (dsc). Measurement results for the enthalpy of combustion were reported previously. The critical temperature was measured with a differential scanning calorimeter. The critical pressure and critical density were estimated. Standard molar entropies, standard molar enthalpies, and standard molar Gibbs free energies of formation were derived at selected temperatures between 298.15 K and 700 K. All results are compared with experimental values reported in the literature.