Systems and methods for quantifying cardiac electrophysiologic signals. An electronic processor receives a unipolar electrogram signal from each of a plurality of electrodes positioned at different locations of a heart. The electronic processor then calculates or measures a bipolar electrogram signal based on a difference between the unipolar electrogram signal for a first electrode and the unipolar electrogram signal for a second electrode. A local activation time (LAT) difference between a location of the first electrode and a local of the second electrode is then determined based on a voltage amplitude of the bipolar electrogram signal. The LAT difference is indicative of an amount of time between a local activation of a propagating wavefront at the location of the first electrode and a local activation of the propagating wavefront at the location of the second electrode.