Mayan Number System

The ancient Maya of Central America created their own number system over 2,000 years ago. It was based on the number 20 instead of 10. They were also one of the first peoples in the world to use a symbol for zero.

Dots and Bars

The Maya used just three symbols to write any number: a dot for 1, a bar for 5, and a shell shape for 0. To write 7, they drew a bar with two dots above it. That is 5 plus 2.

Numbers were written from bottom to top. The bottom row was ones, the next row was twenties, and the row above that was four hundreds. This is similar to how we use ones, tens, and hundreds.

Why Base 20?

Most people think the Maya used base 20 because they counted on both their fingers and their toes. That gives you 20 digits to count with.

The Maya used their number system for trade, building, and their calendar. Their calendar was incredibly accurate. They calculated the length of a year to be 365.242 days, which is amazingly close to the actual value.

Fun Facts

• The Maya had a special calendar called the Long Count that tracked thousands of years.
• Mayan children learned math using cocoa beans as counters.
• The shell symbol for zero is one of the earliest known uses of zero in the world.

Did You Know?

The Maya invented zero completely independently from mathematicians in India. Two different cultures on opposite sides of the world came up with the same amazing idea!