The ancient Maya people were part of a Mesoamerican civilization established in 2000 BC, in what is now known as Central America. Known for their fully developed written language, exceedingly rare in their time, as well as their contributions to art, architecture, mathematics and astronomy, the Mayas are considered one of the first and most evolved civilizations of their time. While primarily an agricultural community, their focus on intellectual development far exceeded that of their neighbors [1-6].

The Mayas were fascinated with astronomy and developed very advanced calendrical systems. The Maya Calendar is a fairly complex system of calendars that accurately predicts the cycles of many celestial bodies [7]. The Maya calendars are essentially refinements and extensions to the earlier developed Mesoamerican calendars [13].

The Maya people used three main calendars, one consisting of 365 days, one of 260 days, and another one to count the years.

The Haab' Calendar (365 Days)

Their 365-day calendar, known as the Haab', was made of up 18 months (called uninals) of 20 days each (called k'ins) to form a 360-day period called the tun. They tacked on another end month of 5 days, called the Uayeb or Wayeb', to form the full 365 day period. The Haab' calendar was a simplified calendar based on the sun that was used for things like planting crops.

The Haab' calendar named each of the 18 months, beginning with Pop and ending with Cumku. The days of each month would be numbered, and used in conjunction with long count to determine the year. Unlike today's calendars, which start numbering at 1, the Haab' began at zero, meaning the last day of the month was numbered 19 rather than 20. The final five days after Cumku were considered bad luck or dangerous. The Mayas had various customs and rituals that they practiced during these days to ward off evil spirits [13].

The Tzolk'in Calendar (260 Days)

Their religious calendar, known as the Tzolk'in or Sacred Round was based on a 260-day cycle. It consisted of a cycle of 20 named days, each with a unique glyph, and a cycle of 13 numerals (depicted as a combination of dots and dashes). This calendar does not follow what you might normally think of as "months" and "days". Instead, the day names and numerals follow a progression like that of two intermeshing gears (one gear with numerals and the other gear with glyphs) [see 7-8].

The progession follows this pattern: 1-Imix, 2-Ik, 3-Akbal, 4-Kan, 5-Chicchan, 6-Cimi, 7-Manik, 8-Lamat, 9-Muluk, 10-Oc, 11-Chuen, 12-Eb, 13-Ben, 1-Ix, 2-Men, 3-Cib, 4-Caban, 5-Etznab, 6-Cauac, 7-Ahau, 8-Imix, 9-Ik, ...

Unlike the Haab' calendar, which was based on the movement of the sun, the reasoning behind the Tzolk'in calendar is still unknown. Some believe it was based on the length of a pregnancy, the amount of time between planting and harvest, or simply based on the religious significance of the numbers 13 and 20.

Each day, depending on the coupling of numbers and names, meant the day was either a bad luck or good luck day. When the 260-day cycle finished, it started over again.

Calendar Round (18,980 Days)

While both the Haab' and Tzolk'in calendars were used for different purposes, they were also used in conjunction with each other. A date described by both calendars would only be the same every 52 Haab' years, providing Mayas with a counting method the spanned about a lifetime. This 18980-day or 52-year period was called the Calendar Round. Anything longer than 52 years had to be described by the Long Count.

The Long Count Calendar (1,872,000 Days)

The Long Count calendar was used by the Mayas to record historical and future dates. Just like the Gregorian calendar counts the days from the year Jesus was born, the Maya Long Count Calendar counts the days from the Maya creation date, which corresponds to August 11, 3114 BC in the current Gregorian calendar.

The Maya long count calendar consists of multiple cycles, not too unlike our day-month-year-decade-millenium system. But, instead of a base-10 system for years/decades/millennia, they used a modified base-20 system (see the table below). For example, 20 solar days or K'ins make up a single Winal (which you might think of as a "month"). The deviation from the base-20 systems comes in next larger cycle, where 18 winals make up a Tun (which is like a 360-day "year"). We're back to base-20 next, with 20 tuns making up a single K'atun. A K'atun is 7200 days, which is a little less than two of our decades. Finally, we have the B'ak'tun, which is 20 K'atuns or 144,000 days.

The long count period consists of 13 baktuns or 260 katuns.

DaysCycles in the Long CountPosition in
Date Format
144,000= 1 B'ak'tun= 20 K'atunBB
7,200= 1 K'atun= 20 TunKK
360= 1 Tun= 18 WinalTT
20= 1 Winal= 20 K'inWW
1= 1 K'in NN

The Long Count dates are written using the format BB.KK.TT.WW.NN. The date 1/1/1900 in today's calendar would correspond to, or 18 + 6*20 + 5*360 + 14*7200 + 12*144000 = 1830738 days since the creation date [see ref. 12].

Dec 21, 2012 AD

Many people are familiar with the special date of December 21, 2012 AD, which marks the end of the long count period of 1872000 days, and corresponds to a winter solstice. The date 12/21/2012 is the first day of the 14th B'ak'tun, or The next long count period simply starts over from that point.

So, saying that the Maya calendar ends on Dec 21, 2012 is somewhat like saying that our calendar ends on December 31, 2012. It will just start over again as the cycle repeats. The main difference is that the Maya calendar is closely tied to the cycles of celestial bodies, and there were always be superstitions when it comes to the positions of the stars and planets.

The Mayas considered the ends of cycles to be times for worry and celebration, just like we do today. Consider how we worried about and celebrated the day 1/1/2000. It was scary because of the Y2K issue and doomsday predictions, but also exciting because of the start of not only a new year, but a whole new millennium.

Combined Calendar Dates

With all of the calendars combined, dates were written as, 3 Cimi 4 Zotz. The portion "" referred to the long count, "3 Cimi" refers to the Tzolk'in date and "4 Zotz" refers to the Haab date.

The Maya calendar system was complex, combining both religion, science and long term planning to provide one of the most accurate systems of their time. The calendars are still used by some civilizations today. The following references provide more information on this intriguing system.

Maya Calendar and Culture References

  1. Coe, Michael D., 1993, The Maya, 5th edition, New York.
  2. The Calendar Explained This article provides detailed information on each of the three Maya calendars, how the whole system worked and the different symbols used.
  3., "The Tzolk'in and Haab" - This article explains and provides visual information on how the religious and vague calendars were joined to create the round calendar Mayas are known for today.
  4. Beyond 2012: Why the World Didn't End This article provides science based, factual answers to the common belief that the Maya long count calendar says the world will end in 2012 – just like the other calendars, the long count calendar simply restarts at this time.
  5. Foster, Lynn V., 2002, Handbook to Life in the Ancient Maya World, New York.
  6. Mesoamerican calendars at

Cite this Article

If you would like to cite this article, please use the following URL in your citation: