Arithmetic operators in PHP

Introduction

Arithmetic operators help you do math with numbers in your program. They let you add, subtract, multiply, and divide values easily.

Calculating the total price of items in a shopping cart.

Finding the difference between two dates or times.

Increasing a score in a game after a player earns points.

Splitting a bill evenly among friends.

Converting units, like inches to centimeters.

Syntax

PHP

$result = $a + $b;
$result = $a - $b;
$result = $a * $b;
$result = $a / $b;
$result = $a % $b;

Use + for addition, - for subtraction, * for multiplication, / for division, and % for remainder (modulus).

Make sure variables hold numbers before using arithmetic operators.

Examples

Adds 5 and 3, then prints 8.

PHP

$sum = 5 + 3;
echo $sum;

Subtracts 4 from 10, then prints 6.

PHP

$difference = 10 - 4;
echo $difference;

Multiplies 7 by 6, then prints 42.

PHP

$product = 7 * 6;
echo $product;

Finds remainder when 10 is divided by 3, then prints 1.

PHP

$remainder = 10 % 3;
echo $remainder;

Sample Program

This program shows all basic arithmetic operations between 15 and 4, printing each result on a new line.

PHP

<?php
$a = 15;
$b = 4;

echo "Addition: " . ($a + $b) . "\n";
echo "Subtraction: " . ($a - $b) . "\n";
echo "Multiplication: " . ($a * $b) . "\n";
echo "Division: " . ($a / $b) . "\n";
echo "Modulus: " . ($a % $b) . "\n";
?>

Important Notes

Division by zero will cause an error, so avoid dividing by zero.

Modulus operator (%) gives the remainder after division, useful for checking even/odd numbers.

Summary

Arithmetic operators let you do basic math in PHP.

Use +, -, *, /, and % for addition, subtraction, multiplication, division, and remainder.

Always check your numbers to avoid errors like dividing by zero.