The Months of the Maya Solar Calendar

The haab is the Maya solar calendar of three hundred and sixty-five days: eighteen months of twenty days each, followed by a short period of five days called Wayeb, regarded as unlucky and dangerous. Each of the eighteen named months (Pop, Wo, Sip, and the rest), runs its twenty days, and the year turns through them alongside the separate 260-day ritual count.

Combined with the 260-day tzolkin, the haab produces the Calendar Round, a cycle of fifty-two years after which a given tzolkin-and-haab date recurs, a fundamental unit of Mesoamerican timekeeping.