PHP ip2long() Function: Usage and Examples

Use ip2long() when you need to converts an IPv4 address into its integer representation in a PHP application. The examples below show the actual operation and its limitations.

What Is ip2long() in PHP?

Converts an IPv4 address into its integer representation. The exact signature supported by your installation depends on its PHP version and enabled extensions.

Its syntax is:

ip2long(string $ip): int|false

Parameters and return value: The parameter types, optional arguments, references, and return type are shown in the signature above. Optional parameters are marked with an ellipsis in this reference signature.

Example 1: Basic Usage

<?php

echo sprintf("%u",ip2long("192.0.2.1"));

Output:

3221225985

Example 2: Different Input or Behavior

<?php

var_dump(ip2long("not-an-ip") === false);

Output:

bool(true)

Practical Example: Applying the Function

<?php

$ipAddress = "203.0.113.5"; $encoded = ip2long($ipAddress); echo $encoded === false ? "Invalid" : long2ip($encoded);

Output:

203.0.113.5

Important Behavior and Edge Cases

Signed integer representations differ across platforms; this function does not handle IPv6.

Comparison With Related Functions

Common Beginner Mistakes

Key Takeaways

• Converts an IPv4 address into its integer representation.
• Signed integer representations differ across platforms; this function does not handle IPv6.
• inet_pton() supports both IPv4 and IPv6 in a packed binary representation.

Use ip2long() for the specific operation demonstrated above. Check its prerequisites and handle failure conditions before using it with production data.