Solubilities of dicyandiamide in five different solvents including water, methanol, ethanol, glycol and acetone were determined at temperature ranging from 273.15 to 338.95 K at atmospheric pressure using a gravimetric method. Fusion enthalpy, Delta H-f, melting temperature, T-m, and the difference in molar heat capacity of the liquid and solid form of dicyandiamide, Delta C-p, were determined by differential scanning calorimetry. On this basis, the ideal solubility of dicyandiamide was calculated, and validity of heat capacity assumptions (specifically, Delta C-p = 0) in predicting the ideal solubility has been evaluated. Further, the measured solubility data was used with the calculated ideal solubility to obtain activity coefficients, which were then fitted to a van't Hoff like regular solution equation. (C) 2013 Elsevier B.V. All rights reserved.