TFM stands for Total Fatty Matter, which is one of the most important characteristics that describe the quality of soap. It is defined as the total amount of fatty matter, mostly fatty acids, that can be separated from a sample after splitting with mineral acid, usually hydrochloric acid. The TFM value is always specified in commercial transactions and is mandatory for toilet soaps to have their TFM content specified as part of their ingredient list. Laundry soaps follow a different criterion and have lower TFM content. The higher the TFM, the more moisturizing properties the soap has, leaving the skin deeply cleansed, yet soft and supple. On the other hand, less TFM means that the soap is damaging to the skin, rips away all the moisture present in the skin, making it dry, and can cause skin sensitivity, rashes, skin breakdown, and infections. The Bureau of Indian Standards (BIS) has segregated toilet soaps into three categories based on the amount of TFM they contain: Grade 1 soaps - minimum 76% TFM content, Grade 2 soaps - minimum 70% TFM content, and Grade 3 soaps - minimum 60% TFM content. One should look for the content of total fatty matter in a toilet soap based on one’s skin type and talk to a dermatologist to help clear doubts and concerns regarding this.