How is fuel air ratio measured?

The fuel-air ratio is measured by comparing the mass or volume of fuel to the mass or volume of air present in a combustion process. This is typically expressed as a ratio, such as 14.7:1 for stoichiometric combustion of gasoline, indicating the ideal proportion for complete combustion. Instruments like mass flow meters, lambda sensors, or fuel flow sensors are used to obtain accurate measurements of both fuel and air. The ratio can also be calculated using engine management systems that monitor engine parameters in real-time.