Back to the interactive abacus

Abacus basics ยท Lesson 2

Reading numbers on an abacus

Read one rod as a digit, then use its position to turn those digits into complete numbers.

Read one rod first

Add the active heaven bead, if any, to the active earth beads. The total is the digit on that rod.

three ones: 3
one five: 5
five + three: 8

Position gives a digit its value

Start at the chosen ones rod and read left. The next rod is tens, then hundreds, then thousands. A 4 on the hundreds rod means 400, not 4.

RodDigitValue
Hundreds4400
Tens220
Ones77
Complete number427

Zeros still hold a place

A cleared rod reads zero, but it cannot be skipped between other digits. In 503, the tens rod is clear. That empty position is what separates 500 from 3.

For decimals, choose a marker as the decimal point. Rods to its right become tenths and hundredths. The same digit-reading rule still applies.