Free Mayan Calendar Converter

The Mayan civilization left behind one of the most sophisticated timekeeping systems ever created. Instead of a single linear calendar, the Maya combined multiple interlocking cycles to record dates with striking precision. This free online Mayan calendar converter acts as a complete Gregorian to Mayan calendar translator, instantly turning any modern date into the corresponding Long Count, Tzolk'in, Haab, and Lord of the Night designations. It also works in reverse, decoding a Mayan Long Count date back into a standard Gregorian date. Whether you are exploring an ancient inscription or simply curious about your birthday in the ancient Maya system, this tool handles all the math behind the scenes.

The Structure of the Ancient Mayan Calendar

Understanding a Mayan date requires grasping four separate but linked calendars. The three main cycles are the Tzolk'in (a 260-day sacred round), the Haab (a 365-day solar calendar), and the Long Count (a linear count of days from a mythological starting point). A fourth component, the Lord of the Night, adds a nine-day cycle of underworld deities. Together they form a unique date string that the Maya carved on stelae and wrote in codices.

The decipherment of these glyphs owes much to the Soviet ethnographer Yuri Knorozov, whose work unlocked the phonetic values of Mayan writing. Thanks to his insights, we can now read the dates left on ancient monuments and convert them into familiar terms.

The Tzolk'in: A 260-Day Sacred Cycle

The Tzolk'in is built from 20 day‑name glyphs and 13 numerical coefficients. Each day is identified by a number (1 through 13) paired with a day name. Because 13 and 20 are coprime, all 260 possible combinations occur before the cycle repeats.

The day names in sequence are: Imix, Ik', Ak'b'al, K'an, Chikchan, Kimi, Manik', Lamat, Muluk, Ok, Chuwen, Eb', B'en, Ix, Men, K'ib', Kab'an, Etz'nab', Kawak, and Ajaw. When the numeral reaches 13, it wraps back to 1 while the name list continues, then the name list also cycles.

The origin of the 260‑day length is still debated. It closely matches the average human gestation period and the growing cycle of maize, suggesting an earthly connection. The number 13 may represent the thirteen layers of the Mayan heaven, while 20 corresponds to the total of human fingers and toes—a reflection of the vigesimal (base‑20) system that pervades Maya numeration. The Tzolk'in is still observed in some highland Maya communities today, influencing decisions such as naming ceremonies and wedding dates.

The Haab: The Solar Calendar

The Haab approximates the tropical year with 18 months of 20 days each, totaling 360 days, followed by a short 5‑day period called Wayeb'. Wayeb' was considered unlucky, a time when the boundaries between worlds were thin.

The 18 months are: Pop, Wo', Sip, Sotz', Sek, Xul, Yaxk'in, Mol, Ch'en, Yax, Sak', Keh, Mak, K'ank'in, Muwan, Pax, K'ayab', and Kumk'u. A Haab date is written as the day number within the month, for example 8 Kumk'u. Unlike the Gregorian system, the Maya did not insert leap days; they noted a drift relative to the astronomical year but chose not to correct it. This means the Haab calendar slowly cycled through the seasons.

The Long Count Calendar

The Long Count is a linear count of days from the Mayan creation date. In the proleptic Gregorian calendar, that starting point is August 11, 3114 BCE, expressed as Long Count 0.0.0.0.0. The system uses a hierarchy of time units:

• 1 k'in = 1 day
• 1 uinal = 20 k'in = 20 days
• 1 tun = 18 uinal = 360 days
• 1 k'atun = 20 tun = 7,200 days
• 1 b'ak'tun = 20 k'atun = 144,000 days

A full Long Count date is written as a dot‑separated sequence of five numbers: B'ak'tun.K'atun.Tun.Uinal.K'in. Higher periods (piktun, etc.) exist but are rarely needed for historical dates.

Converting a Gregorian Date to the Long Count

The converter first computes the Julian Day Number (JDN) of the input date, then subtracts the JDN of the creation date (584,283) to obtain the number of elapsed days $D$. The Long Count components are extracted by successive integer division:

For example, July 17, 2021 (JDN 2,459,413) gives $D = 1,875,130$, which yields the Long Count 13.0.8.12.10—13 b'ak'tun, 0 k'atun, 8 tun, 12 uinal, 10 k'in. The tool performs each of these steps automatically.

The Lords of the Night

A complete Mayan date includes the Lord of the Night, a cycle of nine deities. The day of creation (0.0.0.0.0) corresponds to G1, and each subsequent day advances by one, wrapping after nine. The nine lords and their meanings are:

• G1: Xiuhtecuhtli (Fire Lord)
• G2: Tezcatlipoca (Smoking Mirror)
• G3: Piltzintecuhtli (Prince Lord)
• G4: Centeotl (Maize God)
• G5: Mictlantecuhtli (Underworld Lord)
• G6: Chalchiuhtlicue (Jade is Her Skirt)
• G7: Tlazolteotl (Filth God)
• G8: Tepeyollotl (Mountain Heart)
• G9: Tlaloc (Rain God)

Using the Converter

The Mayan date converter offers two conversion directions:

• Gregorian → Mayan: Choose a date from the calendar or type it manually; for dates before year 1 AD, enable the “BCE” option. The tool instantly displays the Long Count, Tzolk'in, Haab, and Lord of the Night.
• Long Count → Gregorian: Enter five numbers separated by periods (e.g., 12.19.6.1.9) and the corresponding Gregorian date appears.

All calculations are handled by the underlying algorithm, so no manual formulas or tables are needed.

The 2012 Misconception

A widespread rumor claimed that the Maya predicted the end of the world on December 21, 2012. In reality, this date marks the transition from Long Count 12.19.19.17.19 to 13.0.0.0.0—the start of a new b'ak'tun, much like the start of a new millennium. The calendar has no final endpoint; it continues with higher cycles (piktun, etc.). The “apocalypse” was simply a misunderstanding of how the Long Count cycles.

Why Use a Mayan Date Converter?

The complexity of the Mayan calendar—with its overlapping cycles, vigesimal math, and a creation date thousands of years in the past—makes manual conversion tedious and error‑prone. This free online Mayan Long Count calculator and date translator eliminates those hurdles. Whether you’re studying Mayan history, checking the date of an ancient event, or just satisfying your curiosity about your own birthday in the Mayan system, the tool delivers accurate results in seconds.