Generate Random Alphanumeric String with PHP

In this article, we will explain how to Generate Random Alphanumeric String with PHP. This is a simple function that allows you to generate random strings containing Letters and Numbers (alphanumeric) using PHP. The random strings can be used for various purposes, including:

Referral Code
Promotional Code
Coupon Code
OTP Code

Generate Random Alphanumeric String with PHP

Now you can see base on above PHP function we created a random_code() function to generate random alphanumeric string.

function random_code($limit)
{
	return substr(base_convert(sha1(uniqid(mt_rand())), 16, 36), 0, $limit);
}

echo random_code(8);

//Here's the output samples

mocpkwbn
460djcsn
j1m10z0t
4kj9cy68

The above script code relies on following PHP functions:

1. PHP base_convert() Function

The base_convert() function is used to convert a number from one base to another.

Example #1 base_convert() example

<?php
$hexa = 'D174';
echo base_convert($hexa, 18, 8);
?>

Output:

224756

2. PHP sha1() Function

The PHP sha1() function is used to calculate the sha1 hash of a string.

Example #1 sha1() Function

<?php
$str = "Random";
echo sha1($str);
?>

Output:

58d888c08aa561f370e38cee976121532a883d71

3. PHP uniqid() Function

The PHP uniqid function Generate a unique ID.

Example #1 uniqid() Function

<?php
echo uniqid();
?>

Output:

//Here's the uniqid() Function output samples

5b6af218a8eb6
5b6af22304783
5b6af22c4e386
5b6af23fb6bed

4. PHP mt_rand() Function

The PHP mt_rand() function generates a random integer using the Mersenne Twister algorithm.

Example #1 mt_rand() Function

<?php
echo mt_rand();
?>

Output:

//Here's the mt_rand() Function output samples

576535237
1894593969
1647369290
1903411751

Live Demo

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