PHP strrev() Function

Last Updated : 11 Jul, 2025

Reversing a string is one of the most basic string operations and is used very frequently by developers and programmers. PHP comes with a built-in function to reverse strings.

The strrev() function is a built-in function in PHP and is used to reverse a string. This function does not make any change in the original string passed to it as a parameter.

Syntax:

string strrev($inpString)

Parameter: This function accepts a single parameter $inpString. This parameter is a string and it specifies the string which we want to reverse. If a number is passed to it instead of a string, it will also reverse that number.

Return Value: The strrev() function returns the reversed string or the number. It does not make any change to the original string or number passed in the parameter.

Examples:

Input : $string = "geeks" 
Output : skeeg 

Input : $string = 143 
Output : 341

Below programs illustrate the strrev() function in PHP:

Program 1: PHP program to demonstrate the strrev() function when a string is passed.

PHP

<?php
// PHP program to demonstrate the 
// strrev() function when a string is passed 

$str = "geeks";

// prints the reversed string 
echo strrev($str);
?>

Output:

skeeg

Program 2: PHP program to demonstrate the strrev() function when a number is passed.

PHP

<?php
// PHP program to demonstrate the 
// strrev() function when a number is passed 

// passing number instead of string
$num = 134;

// prints the reversed number 
echo strrev($num);
?>