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Kioku Games

Higher or Lower

Find the secret number 1–100 in as few tries as possible. 5 rounds, 60 seconds each.

Higher or Lower

How to Play: Higher or Lower

🎯 Goal

Find the secret 1–100 number in 7 tries or fewer. 5 rounds, 60s each.

🖱️ Mouse / Touch

  • Tap digits on the keypad to enter a guess
  • Tap OK (or press Enter) to submit
  • Read the HIGHER / LOWER hint and narrow the range

⌨️ Keyboard

0–9 / Enter / Backspace Type / submit / delete

💡 Tips

  • Always guess the midpoint of the remaining range
  • 7 guesses are always enough for 1–100

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About Higher or Lower

Higher or Lower (also called the Number-Guessing Game) is one of the oldest and most pedagogically useful games in computer science. Behind its trivial rules lies a perfect demonstration of binary search — the algorithm that lets you locate any item in a sorted million-element list in just twenty steps. Each guess, properly placed, halves the remaining possibilities. With a range of 1 to 100, that means seven guesses are always enough.

In Kioku Games we play five rounds. You have a 60-second clock and seven hearts (one per try) per round. Solve in two tries and you bank +600 plus time bonus; solve in seven and you scrape +200. Five-round perfect runs land in the top 1% of all players.

Why a child can learn binary search from this

The genius of the game is that you do not need to know the word "binary search" to develop the strategy yourself. After two or three guesses where you randomly pick numbers, the realisation hits: "If I always guess the middle of the remaining range, I learn the most from each hint." That insight is the algorithm. From there you instinctively reach 50 → 25 or 75 → and so on, halving uncertainty every step. The game is also a stealth introduction to logarithms, since the number of required guesses grows as log2 of the range size.

There is a competitive edge too. Once you can hit the optimal 7-guess strategy reliably, the only differentiator between players becomes speed — how fast you can do the mental midpoint arithmetic. That moves the game from a thinking puzzle into a reflex one, and that is where it stops feeling educational and starts feeling addictive.