Guess the Number GameHigher-or-lower hints — beat your fewest-guesses record

The classic, endlessly replayable number game

Guess the Number is a simple yet endlessly fun brain game: the computer secretly picks a whole number within a chosen range, and you make one guess at a time. After each guess it tells you only whether your number is "too high" or "too low" until you nail it. There's nothing to download or install — just open the page and play, perfect for a queue, a commute or a quick brain break.

Use binary search to win faster

To win in the fewest guesses, the trick is "binary search": always guess the middle of the remaining range to halve the possibilities each time. For 1–100 you can always win in at most 7 guesses. The tool records how many guesses this round took and your all-time best, so you can keep challenging yourself. To learn the algorithm behind it, see the Wikipedia article on binary search.

Multiple ranges for family fun

Pick 1–10, 1–50, 1–100 or take on the big 1–1000 range depending on the difficulty you want — great as a parent-and-child math game or a contest among friends. When you're done, try our spinner wheel, dice roller and online scoreboard to make gatherings and classroom activities more fun.