Ishango & Lebombo Bones
Interactive tally stick simulator with ancient bone artifacts, notch patterns, prime sequences, and lunar phase counting
Sumerian Counting Board
Mesopotamian counting board with draggable pebbles, base-60 sexagesimal number system, and arithmetic operations
Roman Hand Abacus
Portable bronze pocket abacus with upper quinary and lower unitary beads, Roman numeral conversion
Chinese Suanpan
Classic 2/5 bead abacus with authentic wooden frame, interactive bead sliding, and decimal arithmetic
Japanese Soroban
Streamlined 1/4 bead abacus with practice mode, arithmetic challenges, and step-by-step bead movement guides
Inca Quipu
Interactive knotted cord recording system with color-coded pendant cords, knot types, and positional decimal encoding
Antikythera Mechanism
Interactive gear mechanism with interlocking bronze gears, moon phases, eclipse predictions, and zodiac tracking
Medieval Astrolabe
Interactive brass astrolabe with rotating rete, star positions, altitude/azimuth readings, and ornate astronomical markings