What is Number Guessing Game?

Number Guessing Game challenges you to guess a secret number within a range using as few attempts as possible. After each guess, you get a hint — higher or lower — to narrow down the answer. Choose your difficulty by adjusting the number range, and try to beat your best score.

The optimal strategy is binary search: each guess should split the remaining range roughly in half. On Easy (1–50) the secret is findable in 6 attempts, on Medium (1–100) in 7, and on Hard (1–1000) in 10. Best scores per difficulty are saved on your device, so a streak of disciplined guessing pays off across sessions. Switch on the guess-limit mode to add real stakes, or set a custom range when the presets don't fit.

How to use

1. Select a difficulty level that sets the number range (e.g., 1-50 for Easy, 1-100 for Medium, 1-1000 for Hard).
2. Enter your guess and submit — you'll see whether the secret number is higher or lower.
3. Keep guessing until you find the number. Your attempt count is your score — lower is better!

When to use

• Killing five minutes between meetings without the dopamine drip of social media.
• Teaching a kid binary search the fun way, with no math vocabulary needed.
• Warming up the brain before a mental-math session or interview practice.

Result

A player picks Medium mode (1-100). The secret number is 73. They guess 50 (higher), then 75 (lower), then 63 (higher), then 70 (higher), then 73 — found it in 5 attempts! They challenge themselves to beat that score next round.

FAQ

What's the minimum number of guesses needed in the worst case?

Mathematically, ceil(log2(range)). Easy needs 6 guesses, Medium 7, Hard 10. If you halve the range every time (binary search) you'll hit those limits. A score lower than that means you got lucky on an early guess.

Is the secret number truly random?

Yes, it's drawn from your device's pseudo-random generator (Math.random) when a new round starts. There's no pattern across rounds and no way to recover the secret from past guesses on the same difficulty.

Do my best scores save when I close the tab?

Yes. Best scores per difficulty are saved on your device and reload the next time you open the tool. They stay private — nothing is sent to a server. Use a different device or wipe site data and they reset.

What happens if I type a number outside the range?

It gets rejected without counting as an attempt, so the input always stays inside 1 to the maximum for that difficulty. Letters and decimals are blocked too — only integers in range are accepted.

Why is Hard 10 guesses if there are 1000 numbers?

2 to the power of 10 is 1024, which covers a range of 1000. Each guess cuts the possible answers roughly in half. With perfect bisecting you never need more than 10 questions of 'higher or lower' to nail it.

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