Techniques for adaptively calibrating a TDC output signal in a digital phase-locked loop (DPLL). In an exemplary embodiment, a calibration factor multiplied to the TDC output signal is adaptively adjusted to minimize a magnitude function of a phase comparator output signal of the DPLL. In an exemplary embodiment, the calibration factor may be adjusted using an exemplary embodiment of the least-mean squares (LMS) algorithm. Further techniques for simplifying the adaptive algorithm for hardware implementation are described.