The units of the Maya Long Count

The Long Count is the Maya calendar used for recording dates over long spans, built from nested units: the kin (one day), the winal (twenty kin), the tun (eighteen winal, or three hundred and sixty days), the katun (twenty tun) and the baktun (twenty katun, about three hundred and ninety-four years). A Long Count date is written as a string of these units counted from a fixed starting point in 3114 BCE.

Unlike the cyclical tzolkin and haab, the Long Count is essentially linear, able to fix a date uniquely across thousands of years, which made it the Maya instrument for recording history and dynastic events on monuments.