Abstract: A flow meter and method for determining the corrected flow rate of a liquid falling into a predetermined class of liquids based on its viscosity and density is disclosed. The flow meter comprises a flow sensor for measuring an uncorrected flow rate of the liquid, a temperature sensor for measuring the temperature of the liquid, and a microprocessor for calculating the corrected flow rate based on the liquids predetermined class and the measured temperature. The flow sensor can include a restriction in the fluid flow path, first and second pressure sensors positioned one on each side of the restriction and a temperature sensor. The first and second pressure sensors measure the drop in fluid pressure created by the restriction and the temperature sensor measures the temperature of the liquid. By basing the corrected flow rate calculation on the predetermined class of the liquid, the calculation becomes a closed form solution that is deterministic providing for quick and accurate corrected flow rate calculation.