Abstract The out-of-time-order correlator (OTOC) is considered as a measure of quantum chaos. We formulate how to calculate the OTOC for quantum mechanics with a general Hamiltonian. We demonstrate explicit calculations of OTOCs for a harmonic oscillator. a particle in a one-dimensional box. https://www.jmannino.com/mega-pick-NFL-San-Francisco-49ers-Zone-Block-iPhone-14-Pro-MagSafe-Case-p80213-quick-pick/