This paper proposes a feedforward quasi universal converter for energy harvesters, and uses it to power loTs (Internet of Things). A typical DC/DC converter uses voltage feedback control or current feedback control. It is difficult to meet its output voltage and power targets and have its input impedance stay as close to the output impedance of the energy source as possible. The proposed feedforward quasi universal converter allows the input/output parameters of the DC to DC converter in the energy harvester to loosely follow the variation of the energy source output parameters. It controls the DC to DC converter input impedance and output voltage/power to vary within a range that meets the design targets by either adaptively or manually adjusting the circuit parameters. It also allows a system designer to trade off precision for flexibility/simplicity in each unit of the harvester to achieve an optimum design. This paper uses a boost converter to present the feedforward quasi universal converter concept, discusses the cases that may cause overvoltage/overcurrent conditions, and provides the analysis for choosing proper design parameters to avoid them. (C) 2017 Elsevier Ltd. All rights reserved.