Energetic compounds are substances containing metastable molecules capable of undergoing very rapid and highly exothermic reactions and determination of their properties is likely to be expensive or dangerous with environmental problems. A simple and reliable method is introduced for desk calculations of the enthalpy of fusion of different energetic compounds with general formula CaHbNc,(O or S)(d)(halogen)(e). This method is based on two simple models, which require only elemental composition and specific polar groups or molecular fragments. The first model requires only the number of used atoms, which is improved by some molecular moieties in the second model. For 91 different energetic compounds (corresponding to 123 measured values), the predicted results of two simple models are more reliable than several of the best available methods. The second model provides more reliable results with respect to the first one and can be easily applied for energetic compounds with complex molecular structures. (C) 2012 Elsevier B.V. All rights reserved.