PHP strcmp() Function: Usage, Parameters, Return Values, and Examples

The PHP strcmp() function compares two strings in a binary‑safe, case‑sensitive manner and returns an integer indicating their lexical relationship.

Parameters string $str1: The first string. string $str2: The second string.

Return values

Less than 0 if $str1 is less than $str2.

Greater than 0 if $str1 is greater than $str2.

0 if the strings are equal.

Example 1

<?php
echo strcmp("Hello", "Hello");
echo "<br>";
echo strcmp("Hello", "hELLo");
?>

Output:

// 0
// < 0 (because "Hello" is less than "hELLo" in binary comparison)

Example 2

<?php
echo strcmp("Hello world!", "Hello world!"); // strings are equal

echo strcmp("Hello world!", "Hello"); // $str1 > $str2
?>

Output:

// 0
// positive integer (e.g., 7)