MayanHead JC's Decimal-to-Mayan Converter MayanHead

Enter a nonnegative decimal integer:
Glyph orientation: vertical horizontal
Text layout: vertical horizontal

Mayan writing made free use of both horizontal and vertical layouts, frequently mixing both together in complicated ways. Numbers were written with both orientations, usually vertical for horizontal layouts and vice versa. Numbers were also routinely merged in with glyphs for words, in whatever fashion was considered most aesthetically pleasing to the scribe. Our default is consistent with English orthography, but you can select other combinations to see what they look like.

Mayan numbers are simple. The notation is base 20. A "digit" consists of 1-3 lines that have the value 5, plus 1-4 dots that have the value 1. An empty place is represented with a circle or oval, often drawn to represent a clam shell. Mayan merchants would use a row of shells or carved depressions in a piece of wood to represent the places, with sticks and pebbles or beans to represent the digits. Arithmetic was similar to using an abacus.

To be added some day: Pretty images of classical Mayan carved numbers.

Links to related sites
Mdate is a utility that converts Gregorian dates to Mayan Long Count dates. Maybe I should include a web interface to it here ....
has a good collection of links to Mesoamerican web pages. They also have a good introduction to the Mayan writing system.
The Mayan Epigraphic Database Project (MED)
is an experiment in networked scholarship with the purpose of enhancing Classic Mayan epigraphic research. (Description taken from their page.) They have a growing catalog of Mayan glyphs, and a growing assortment of educational and research material.
The Maya Calendar
at the Maya World Studies Center in Merida, Yucatan, Mexico, is a good description of how the Mayan calendar worked, complete with a calendar conversion page.
is James Jacobs' collection of images of Mayan stelae and codices.
If you know of other links that would be good to add to this list, send me email.