A device for testing low dropout (LDO) regulator is disclosed. In one embodiment, a device for testing LDO regulators includes an absolute value measurement module for measuring absolute output voltages of the LDO regulators including a resistor scaling array for generating candidate voltages based on a first output voltage of the LDO regulators, a multiplexer for forwarding one of the candidate voltages selected by a binary search algorithm, and a comparator for generating a first test output by comparing the candidate voltage with an external reference voltage, and a DC load regulation measurement module for measuring corresponding DC regulation voltages of the LDO regulators including a switch for applying an internal test load to a second output voltage of the LDO regulators, and the comparator for generating a second test output by comparing a reference voltage with the second output voltage modified by the internal test load.