Abstract: A fuel analyzer for a fuel dispensing environment is provided including an ultrasonic transmitter configured to transmit an ultrasonic signal through a volume of fuel, an ultrasonic receiver configured to receive the ultrasonic signal, and processing circuitry. The processing circuitry is configured to receive an indication of transmission of the ultrasonic signal from the ultrasonic transmitter, receive an indication of receipt of the ultrasonic signal from the ultrasonic receiver, determine a time of flight of the ultrasonic signal, and determine a fuel purity based on the time of flight of the ultrasonic signal.