Build a Number Guessing Game in Python

A classic first game

The number guessing game is the "hello world" of game programming. The computer thinks of a secret number, you try to guess it, and after each guess it tells you whether to go higher or lower. It is short enough to finish in one sitting but uses real programming ideas you'll reuse forever: loops, input, comparisons and conditions.

If you've already written your first Python program, you have everything you need. Let's build it piece by piece, then put it all together.

Step 1: pick a secret number

The computer needs to choose a number the player can't predict. That is exactly what the random module is for:

import random

secret = random.randint(1, 100)

random.randint(1, 100) returns a whole number from 1 to 100, with both ends included. Because it's random, every game is different. (For a deeper look at randomness, see random numbers and games in Python.)

Step 2: ask the player to guess

We use input() to read what the player types. But input() always gives back text, and you can't compare text with a number, so we wrap it in int():

guess = int(input("Guess a number from 1 to 100: "))

If the player types 42, then guess becomes the number 42, ready to compare.

Step 3: give a hint

Now compare the guess with the secret and react:

if guess < secret:
    print("Too low! Try higher.")
elif guess > secret:
    print("Too high! Try lower.")
else:
    print("Correct!")

The if/elif/else handles all three cases: below, above, or spot on. (Need a refresher? See making decisions with if.)

Step 4: keep asking with a loop

One guess isn't a game. We want to keep asking until the player wins, so we wrap the asking and hinting in a while True: loop and break out when correct:

while True:
    guess = int(input("Your guess: "))
    if guess < secret:
        print("Too low!")
    elif guess > secret:
        print("Too high!")
    else:
        print("You got it!")
        break

while True: means "loop forever" — until something stops it. The break is that stop: it fires only when guess == secret.

The complete game

Here is the whole thing, with a guess counter and a replay option so it feels finished:

import random

def play_round():
    secret = random.randint(1, 100)
    guesses = 0
    print("I'm thinking of a number between 1 and 100.")

    while True:
        guess = int(input("Your guess: "))
        guesses += 1

        if guess < secret:
            print("Too low! Try higher.")
        elif guess > secret:
            print("Too high! Try lower.")
        else:
            print(f"Correct! The number was {secret}.")
            print(f"You found it in {guesses} guesses.")
            break

# Main game loop with replay
print("=== NUMBER GUESSING GAME ===")
while True:
    play_round()
    again = input("Play again? (yes/no): ").lower()
    if again != "yes":
        print("Thanks for playing!")
        break

What each part does:

1. play_round() runs one complete game: pick a secret, loop until guessed, count tries.
2. guesses += 1 is short for guesses = guesses + 1. It counts every attempt.
3. The outer while True: lets the player start a fresh round. .lower() makes the answer lowercase so YES, Yes and yes all work.
4. If they type anything other than yes, we break and say goodbye.

A sample run looks like:

I'm thinking of a number between 1 and 100.
Your guess: 50
Too high! Try lower.
Your guess: 25
Too low! Try higher.
Your guess: 37
Correct! The number was 37.
You found it in 3 guesses.
Play again? (yes/no): no
Thanks for playing!

The winning strategy

Always guess the middle of the remaining range. Start at 50. If it's "too high", the answer is 1–49, so guess 25. If "too low", guess 75. Each guess cuts the possibilities in half, so you can win in 7 guesses or fewer every time. This trick is called binary search, and it's one of the most important ideas in computing.

Try it yourself

Upgrade your game with these challenges:

• Add difficulty levels. Ask the player to pick easy (1–20), medium (1–100) or hard (1–1000) and set the range with an if/elif/else before picking the secret.
• Limit the guesses. Give the player only 7 tries. Count them, and if they run out, reveal the number and print "Game over!" Use a while loop condition like while guesses < 7:.
• Track a high score. Remember the fewest guesses across rounds and print it at the end.
• Reverse it. Make you think of a number and let the computer guess, always picking the middle of its range. Watch binary search in action!