A system for determining a viscosity of a fluid is provided. The system includes an intake chamber, a tube, a piston, an actuator, a sensor, and a processor. The tube communicates with the intake chamber and includes a channel including a cylindrical portion with a constant diameter cross section. The piston is mounted in the intake chamber. The actuator is configured to move the piston within the intake chamber at a constant speed during a time window to regulate a fluid in the cylindrical portion. The sensor is configured to measure a pressure a plurality of times during the time window to define a plurality of pressure measurements. The processor is configured to receive the defined plurality of pressure measurements, to determine a slope associated with the received plurality of pressure measurements, and to determine a viscosity of the fluid based on the determined slope.