Free Online Abacus
A soroban you can use right here: tap a die to move it. The top dice are worth 5, the bottom dice are worth 1, and a die counts when it touches the bar.
How to use the online abacus
Every rod is one place value. The rod on the right is the ones, the next rod is the tens, then hundreds, thousands and so on. The little white dots on the bar mark every third rod, so big numbers are easy to read.
To show 7 on the ones rod, bring the top die (5) down to the bar and push two bottom dice (1 + 1) up to it. To show 0, move every die away from the bar. The number under each rod tells you its digit while you learn; switch Numbers off to practice reading the beads yourself.
More abacus tools
For younger children, the counting frame (ten rows of ten beads); for 1st and 2nd grade, the place value abacus; and printable abacus worksheets with answer keys.
Learn it step by step
New to the abacus? The free abacus lessons start from zero with PlayBuddy and PlayType, show every move on this same abacus and check yours.
Questions and answers
How do I read the abacus?
A bead counts only when it touches the bar in the middle. The top die on each rod is worth 5, each bottom die is worth 1. Add up the dice touching the bar on a rod to get that rod’s digit: the top die and two bottom dice make 7. The rods are places: ones on the right, then tens, hundreds and so on.
Why are the beads dice?
So the value is on the bead itself: the top die shows five dots and the bottom dice show one dot each. Children can see why the top bead is worth 5 without being told twice. It works exactly like a Japanese soroban: one bead above the bar, four below.
Can I use it without a mouse?
Yes. Press Tab to reach the abacus, use the left and right arrows to pick a rod, the up and down arrows to add or take away one, or type a digit to set that rod. The number on the abacus is also read out to screen readers.
Is it free?
Yes, completely free, with no account and no ads. Nothing you do on the abacus leaves your device.