Binary Cards
Think of a number from 1 to 63. Just say whether it is on each of six cards, and the number is guessed.
Card 1 of 6
3233343536373839404142434445464748495051525354555657585960616263
Is your number on this card?
How to play
Pick a number from 1 to 63 in your head. Cards appear one at a time. Tap "Yes" if your number is on the card, or "No" if it is not. After six cards, your number is revealed.
Learn more
The top-left numbers of the cards are 32, 16, 8, 4, 2 and 1. Add up the top-left numbers of the cards you said "Yes" to, and you get your number. Every number has exactly one combination of cards. This is binary (writing numbers with only 0 and 1): each card is one binary digit. Computers store numbers this way.