Kin, the Single Day

The kin is the base unit of the Maya Long Count, the great linear calendar the Maya used to fix dates across vast spans of time rather than within a repeating cycle. A kin is a single day. The Long Count builds larger units from it in a mostly base-twenty scheme: twenty kins make the next unit up, and successive units multiply by twenty, with one deliberate exception at the third level to keep the count close to the solar year. A Long Count date is written as a string of these units counted from a fixed mythic starting point, the creation date the inscriptions give as 4 Ajaw 8 Kumku. The kin is thus the atom of the whole system. These are the features of the Maya Long Count, the timekeeping framework carved on the monuments of the Classic period to record the reigns and rituals of the Maya lords.

The Kin is the base unit of the Maya Long Count, a single solar day, and the Long Count itself is a positional, largely base-20 (vigesimal) tally of elapsed days written as five place values, Baktun.Katun.Tun.Winal.Kin, running for example 13.0.0.0.0. Long Count dates are attested in monumental inscriptions from the Preclassic period onward, with the earliest securely dated examples from sites such as Chiapa de Corzo and Tres Zapotes in the last centuries BCE, predating the Classic Maya cities where the system is best known. Because the count is a simple linear tally from a fixed starting point rather than a cycle that repeats, it can in principle run indefinitely, and it is the only calendar among the Mesoamerican systems capable of specifying a date uniquely across long spans rather than only within a repeating 52-year or 18,980-day round.