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How to read numbers on an abacus
One rule, one sum: count 5 for the top bead if it touches the beam, then add 1 for each bottom bead touching it.
Reading one rod
Each rod is worth 5 if the heaven bead is down, plus 1 for every earth bead pushed up. Beads that are away from the beam do not count at all. Here is every digit, one per rod:
| Digit | Heaven bead (5) | Earth beads (1 each) |
|---|---|---|
| 0 | up | none |
| 1–4 | up | that many pushed up |
| 5 | down | none |
| 6–9 | down | digit minus 5 pushed up |
Reading a whole number
Find your ones rod (a unit point helps), then read the rods from left to right, exactly as you read a written number.
Setting a number
To put a number on the board, clear it first, then work from the left. On each rod, push earth beads up with your thumb and move the heaven bead with your index finger. For 6, 7, 8 and 9 you need both — move them together as one pinch rather than one after the other. The finger technique guide covers this in detail.
Try these
Cover the answer, read the board, then check.
What number is this?
68
What number is this?
204
What number is this?
7591
Common slips
- Counting beads that are not touching the beam. Only beads pushed against the beam count — the others are just parked.
- Forgetting the zeros. An empty rod in the middle of a number is a real 0. Skip it and 305 becomes 35.
- Reading right to left. Read the way you write: biggest place on the left.
Ready to try it?
Practise reading the board →Common questions
How do you show zero on an abacus?
A rod shows zero when no bead touches the beam: the heaven bead is pushed up and all four earth beads are pushed down.
Which rod is the ones rod?
Any rod you choose. Most people pick a rod with a unit point (a dot on the beam) so they can find the thousands and decimal places easily.
How do you show 9 on a soroban?
Push the heaven bead down (5) and all four earth beads up (4). Every bead on the rod touches the beam.