Creating perfumes through reverse engineering with analytical techniques such as GC/MS can reveal the "general" formula for any particular perfume. The difficult of GC/MS analysis arise due to the complexity of a perfume's ingredients, this is particularly due to presence of natural essential oils and other ingredients consisting of convoluted chemical mixtures. However, "anyone armed with gratifying GC/MS equipment and experienced in using this equipment can today, within days, find Cologne out a great deal about the formulation of any perfume... customers and competitors can analyze most perfumes more or less precisely."

Antique or badly preserved perfumes undergoing this analysis can also be difficult due to the numerous degradation by-products and impurities that may have resulted from breakdown of the odorous compounds. Ingredients and compounds can mostly be ruled out or identified using gas chromatograph (GC) smellers, which allow individual chemical components to be identified both through their physical properties and their scent.