Illustrative embodiments of positive displacement pumps utilizing pressure compensating calibration, as well as related systems and methods, are disclosed. In one illustrative embodiment, a method of operating a positive displacement pump includes sensing, with a pressure sensor disposed at a fluid outlet of the positive displacement pump, a back pressure at the fluid outlet, transmitting a pressure signal associated with the sensed back pressure from the pressure sensor to a controller of the positive displacement pump, and identifying, on the controller, a volume of fluid pumped by the positive displacement pump using the pressure signal.