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How to Create a Number Guessing Game in Batch Script

Writing simple, interactive games is one of the most effective ways to understand a new scripting language. A "Number Guessing Game" incorporates several critical programming fundamentals: generating random numbers, establishing continuous while-style loops, evaluating numeric comparisons, and accepting user input.

In this guide, we will build a classic Number Guessing Game natively within the Windows Command Prompt using a Batch script.

The Strategy: The %RANDOM% Variable​

  1. Generate a target number between 1 and 100 using the built-in %RANDOM% environment variable.
  2. Initialize a "guess counter" variable to 0.
  3. Create an infinite loop labeled :GuessLoop.
  4. Prompt the user for an integer inside the loop.
  5. Provide feedback ("Too High" or "Too Low").
  6. Break the loop and display the total guesses when the user guesses the target.

Implementation Script​

@echo off
setlocal EnableDelayedExpansion

title Guess The Number
color 0B

:NewGame
cls
echo ==========================================
echo        WELCOME TO GUESS THE NUMBER
echo ==========================================
echo I am thinking of a number between 1 and 100.
echo Can you guess what it is?
echo.

set /a "target=(!RANDOM! %% 100) + 1"
set "attempts=0"

:GuessLoop
set "userGuess="
set /p "userGuess=Enter your guess (1-100): "

:: -------------------------------------------------------
:: Validation Step 1: Non-empty
:: -------------------------------------------------------
if not defined userGuess (
    echo Please type a number.
    goto GuessLoop
)

:: -------------------------------------------------------
:: Validation Step 2: Digits only (using findstr)
::   echo( is a batch trick that safely prints any value
::   No space before | so no trailing space is piped
:: -------------------------------------------------------
echo(!userGuess!| findstr /r "^[0-9][0-9]*$" >nul
if errorlevel 1 (
    echo Invalid input. Please enter numbers only.
    goto GuessLoop
)

:: -------------------------------------------------------
:: Validation Step 3: Range check
:: -------------------------------------------------------
if !userGuess! lss 1 (
    echo Out of range. Enter a number between 1 and 100.
    goto GuessLoop
)
if !userGuess! gtr 100 (
    echo Out of range. Enter a number between 1 and 100.
    goto GuessLoop
)

:: -------------------------------------------------------
:: Increment attempts
:: -------------------------------------------------------
set /a "attempts+=1"

:: -------------------------------------------------------
:: Evaluate the guess
:: -------------------------------------------------------
if !userGuess! gtr !target! (
    echo   -^> Too High! Try a lower number.
    echo.
    goto GuessLoop
)

if !userGuess! lss !target! (
    echo   -^> Too Low! Try a higher number.
    echo.
    goto GuessLoop
)

:: -------------------------------------------------------
:: Correct guess
:: -------------------------------------------------------
echo.
echo ==========================================
echo             CONGRATULATIONS!
echo ==========================================
echo You correctly guessed the number !target!
echo It took you !attempts! attempts.
echo.

set "replay="
set /p "replay=Play again? (Y/N): "
if /i "!replay!"=="Y" goto NewGame

echo Thanks for playing!
pause
exit /b

How It Works​

  1. Random Generation (%%): The expression set /a "target=(!RANDOM! %% 100) + 1" is fundamental. The modulo operator %% divides the %RANDOM% integer (0–32767) by 100 and returns the remainder (0–99). Adding 1 shifts the range to 1–100.
  2. Numeric Comparisons (lss/gtr): In Batch, if you try to evaluate if %userGuess% > %target%, Windows throws a syntax error because > is the file-redirection symbol. You must use gtr (Greater Than), lss (Less Than), and equ (Equal To) when evaluating numbers.
  3. Input Validation via Digit Stripping: The script removes every digit character (0–9) from the user's input. If any characters remain after stripping, the input contained non-numeric characters and the user is re-prompted. This avoids the pitfalls of relying on set /a for validation, which silently evaluates environment variable names and expressions rather than rejecting them.

Why Build a Guessing Game?​

  1. Math Operators: It forces a developer to understand how to correctly evaluate integers versus strings.
  2. Defensive Programming: Handling human input is chaotic. A guessing game forces handling edge cases: What if they hit "Enter" without typing anything? What if they type a letter?
  3. Loop Management: Learning how to effectively utilize goto structure to simulate do...while loops allows for complex logic iterations required in corporate script polling.

Conclusion​

Creating a Number Guessing Game provides a fantastic, low-stakes environment to master Windows Batch's math evaluations, variable scopes, and iterative loops safely. Navigating dynamic variables and guarding against unexpected user inputs transforms an otherwise mundane script command into a fully fledged, interactive local software experience.

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