Convert between modern decimal numbers and the ancient Mayan base‑20 (vigesimal) system — with arithmetic, a calendar converter, charts, a live clock and a quiz.
Add, subtract or multiply two numbers and see the answer written in Mayan numerals. The Maya added by simply piling dots and bars together, then "carrying" every time a place reached 20.
The Maya tracked time with three interlocking systems:
Conversions use the standard GMT correlation (584283).
Hours, minutes and seconds are each shown as a proper base-20 numeral. Values above 19 stack into two places (e.g. 47 seconds = 2·20 + 7, written as 2 over 7).
Read the Mayan numeral and type its decimal value. Pick a difficulty to change the range.
Every Mayan digit is built from a shell (0), dots (1 each, up to four) and bars (5 each, up to three). Dots sit above bars.
The Maya civilization developed a vigesimal (base-20) number system using just three symbols:
Numbers 1–19 combine up to four dots and three bars. Larger numbers stack vertically, with each place worth 20× the one below it (the ones place sits at the bottom).
The pure numeral system multiplies by 20 at every step (1, 20, 400, 8000…). The Long Count calendar makes one exception — the third place (the tun) is worth 360, not 400, so that a tun closely matches a solar year. This tool keeps the two systems correctly separate.