Bead by Bead

Six rounds a game, a little harder each time you play again.
Set a number: tap a bead to push it to the beam, or back; the beads between go with it. You can also swipe on a rod. Then press Done.
Read a number: tap the card that matches the abacus.
Add: set the first number, then push the second onto it. Trade five ones for the five-bead, and carry ten to the rod on the left (Abacus help shows how).

With a keyboard, pick a rod with Tab or the arrow keys, push lower beads with up and down, and move the five-bead with Enter.

A bug, a puzzle that felt unfair, an idea? Tell us: we read everything.

More like Bead by Bead

Numbers, Practice
Old Money
Pay real prices from Samuel Pepys’s diary in pounds, shillings and pence: tap coins onto the counter and watch twelve pence turn into a shilling.
about 4 minEarly version
In English
Play
Numbers, Practice
Numbers in Stone
Read and write numbers the way they were carved and pressed: Roman letters on stone, Babylonian wedges in clay, Egyptian hieroglyphs, Greek letters and Maya bars and dots.
about 5 minEarly version
In English
Play
Numbers, Practice
Same Number, Many Scripts
Read the digits people write today, from Arabic and Devanagari to Thai, and build numbers from Chinese characters.
about 4 minEarly version
In English
Play
Numbers, Daily
Knot Count
Read and tie numbers in knots on khipu cords, the way Andean record keepers did.
about 4 minEarly version
In English
Play
Set, 238–1669
Keeping Time
How people named the months and days, fixed the year and kept a diary
LatinEarly Modern English
Set, 450 BCE–500
Kitchen, Farm and Fable
Recipes, farm work, animals, fables and lessons in Greek, Latin, Chinese and Japanese
Classical ChineseGreekLatin