A handy calculator for calculating the pressure drop (head loss) of a fluid in a circular pipe due to friction. The app includes a database of the most commonly used pipe configurations, such as nominal, standard, and metric. It also provides a variety of commonly used physical parameters, such as the pipe roughness and the flow rate. The user can choose from several different types of fluids, including gas, liquid, and snow.

The head loss is calculated by means of a Darcy-Weisbach equation, while the friction factor is calculated using a different approach, depending on the flow characteristics of the pipe. If the flow is laminar, then the f=64/Re formula is used, where Re is the Reynolds number. If the flow is more than laminar, then an approximation of the Colebrook equation is used. In this case, the f=K/Re^(1/3) is used, where K is the kinetic viscosity of the fluid. If the flow is turbulent, then an f=16/Re^(1/2) is used, where Re is the Reynolds number.