A method and an apparatus utilizing a digital computer programmed for the purpose to perform a virtual combination of potential source chemicals, found in a raid or a chemical cache, for the manufacture of Homemade Explosives (HMEs), so as to transform the raw inventory of found chemicals quickly and accurately into a readily understandable output predicting the various HME formulations whose manufacture was contemplated by a would-be bomb maker, along with an assessment of the relative likelihoods of each such possible HME outcome.