Soroban Calculation

Move the soroban's beads with your finger to build numbers and get a real feel for calculation.

SOROBAN
Drag the beads on the on-screen abacus and the current number shows large as you go. Full-featured: you can even choose which column is the ones place (fixed-point marker). Clear, undo, and toggle the result display — use it as freely as a calculator.

PRACTICE
Pick a grade (10 kyu, easiest, through 1 kyu, hardest) and a type — addition & subtraction, multiplication, or division — then solve 10 questions. The abacus board stays on screen, so you can move real beads while you work. Each answer is checked the moment you enter it, with a full score at the end.

RECORDS
Every practice run is saved automatically — date, grade, type, and number correct. A perfect score gets its own special mark. Seeing your progress makes it easier to keep going.

WHO IT'S FOR
Kids currently learning soroban, and kids just starting out. Adults who want to practice calculation or mental arithmetic in spare moments. Parents who want to explore numbers together with their kids.

FEATURES
No ads, no in-app purchases. No account required, and no personal information (like your name) is collected. Supports dark mode, and displays in both Japanese and English.

Problems are not a strict reproduction of any official soroban certification exam's standards — use grades as a general guide only.