Free soroban lessons
Learn the abacus
Step-by-step guides with pictures, for children learning the Japanese soroban and the grown-ups helping them. Every worked example shows the exact beads to move and the finger to move them with.
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What is an abacus?A counting frame where beads stand for numbers — and, in practised hands, one of the quickest ways there is to do arithmetic without a calculator.The parts of a sorobanFive parts and one rule to remember: a bead only counts when it touches the beam.How to read numbers on an abacusOne rule, one sum: count 5 for the top bead if it touches the beam, then add 1 for each bottom bead touching it.Abacus finger techniqueTwo fingers, each with a fixed job. It feels fussy for a week, then it is what makes you fast.Abacus for kids: a parent’s guideYou do not need to know the abacus yourself. You need ten minutes a day and a sensible order to learn things in.
Adding and taking away
Abacus addition and subtractionSet the first number, then add or take away the second one digit at a time. There are only five kinds of move, and this guide shows each one.Little friends: the 5 complementsWhen there is no room for a small number, add 5 and give its little friend back — in one movement.Big friends: the 10 complementsA rod can only hold 9. When a sum spills over, take off the big friend here and carry a 1 next door.Big numbers on the abacusSame five moves, more rods. Work the digits from left to right and let each rod look after itself.
Multiplying and dividing
Going further
Decimals on the abacusAdding decimals needs nothing new. Multiplying and dividing need one short rule to find the ones rod of the answer.Anzan: the abacus in your headThe same bead moves, done on an imaginary board. It is where abacus practice leads.Abacus glossaryEvery abacus word used on this site, in plain English.