The rock salt-type transition metal carbides and nitrides are excellent refractory materials as well as important microstructural constituents in High Strength Low Alloy (HSLA) steels. Therefore, it is important to have knowledge on their elastic, thermophysical and thermochemical properties in order to gain deeper understanding of their role in these contexts. In this paper we report their mechanical properties such as the elastic constants, various moduli, Poisson's ratio and cleavage energies, thermochemical properties such as the energy of formation and cohesive energy and physical properties such as the p-V relation, first derivative of bulk modulus with respect to pressure, Debye temperature and the heat capacity determined using first principles calculations. Wherever possible, corresponding experimental data have been compared with and a good agreement is seen. © 2013 Elsevier B.V. All rights reserved.