Guess the Number (Higher or Lower)Free, no sign-up

Guess the secret number within the range and enter it. You'll get a hint — higher or lower — so use it to narrow down the range until you find the number.

Binary search, always guessing the exact middle, is the most efficient: it always finds the number within 7 guesses for 1–100, 10 for 1–1,000 and 14 for 1–10,000.

Yes. All three ranges change at midnight Japan time. Random practice uses a different number each time and isn't recorded.

By the number of guesses, fewest first; ties go to the shorter time. You only need a nickname, and you can submit up to 30 times a day per range. The server checks your list of guesses.