The Mayan Calendar Explained

The Maya used several calendars that worked together, not a single calendar. The main ones were the Tzolkin, the Haab and the Long Count. The Tzolkin and the Haab combined into a longer cycle called the Calendar Round.

Each count did its own job. The Tzolkin named each day for ceremonies, and the Haab followed the solar year. The Long Count placed an event in history, much like our year numbers. Carved dates usually give the Long Count first, then the Calendar Round.

The Maya also watched the Sun, the Moon and Venus to keep their counts in step. Our Maya astronomy guide explains those sky cycles.

The Tzolkin calendar is a 260-day ritual calendar. It pairs 20 day signs with the numbers 1 to 13, so each of its 260 days has its own name and number.

Both parts move forward by one each day. The count runs 1 Imix, 2 Ik, 3 Akbal and on to 13 Ben. Then the number goes back to 1 while the signs keep going, so the next day is 1 Ix. A pair such as 4 Ajaw comes back only after 260 days.

The Tzolkin set the days for ceremonies, and each day sign carried its own meaning. The table uses common Yucatec Maya spellings. Some sources use highland Maya names instead, such as Tzikin for Men and Tijax for Etznab.

The Haab calendar is the 365-day solar year of the Maya. It has 18 months of 20 days each. Five extra days at the end, called the Wayeb, bring the total to 365.

Days in each month are numbered 0 to 19. The day numbered 0 is called the seating of the month, so the year runs 0 Pop, 1 Pop and on to 19 Pop, then 0 Wo. The Maya thought of the five Wayeb days as an unlucky, risky time.

The Haab has no leap day. It slowly drifts against the seasons, by about one day every four years.

The Calendar Round is the 52-year cycle formed by the Haab and the Tzolkin. A Calendar Round date names a day in both calendars, such as 4 Ajaw 8 Kumku. The same pair of days returns only when both cycles realign, every 52 years.

The two counts line up again after 18,980 days. That is 73 runs of the Tzolkin and 52 Haab years.

The Haab year moves five Tzolkin days forward each time, because of the five Wayeb days. As a result, only four of the 20 day signs can fall on a Haab new year. These four signs are called Year Bearers.

The Mayan Long Count calendar counts days from a mythical start date in 3114 BC. It let the Maya record dates across very long periods of history. At Chichen Itza, a lintel at the Initial Series Temple carries a Long Count date equal to July 30, 878 CE.

A Long Count date has five numbers, written from the largest unit to the smallest. Most units hold 20 of the unit below. The tun is the exception: it holds 18 winal, or 360 days, close to a solar year.

The start date was 13.0.0.0.0 4 Ajaw 8 Kumku. Matching it to our calendar needs a correlation, and researchers still debate the exact one. The correlation most researchers use places the start on 11 August 3114 BC, and a close variant gives 13 August.

Your Maya birthday is usually your Tzolkin day: one of the 20 day signs with a number from 1 to 13. To find it, start from a date you know, such as 21 December 2012, which was 4 Ajaw.

Count the days from that date to your birth date. Each day adds one to the number, and after 13 it goes back to 1. Each day also moves the sign one step down the table, and after Ajaw it returns to Imix. So 22 December 2012 was 5 Imix.

Because the count repeats every 260 days, you can divide a long count of days by 260 and step through only what is left over. Highland Maya tradition links the day sign of birth with a spirit companion, or nahual. The result can shift by a day or two, depending on the correlation used.

The Maya calendar did not predict the end of the world in 2012. The end of a Long Count cycle in December 2012 marked a new era for the Maya, not an ending.

On 21 December 2012, the Long Count reached 13.0.0.0.0, the end of the 13th bak'tun. That was about 5,125 years after the start date. For the Maya, time moved in cycles. The next day was the first of a new bak'tun, and the count simply carried on.

Many Maya communities in the highlands of Guatemala still keep the Calendar Round today. Local spiritual guides use its 260-day count of day signs to choose days for ceremonies.

Each region keeps its own names for the day signs, such as Batz for the sign called Chuwen in Yucatec Maya. The Long Count is no longer kept as a daily calendar. You see it today on carved monuments, such as the lintel at Chichen Itza, and in the dates scholars read from them.