PHP inet_ntop() Function: Usage and Examples

Use inet_ntop() when you need to converts a packed binary IPv4 or IPv6 address into readable text in a PHP application. The examples below show the actual operation and its limitations.

What Is inet_ntop() in PHP?

Converts a packed binary IPv4 or IPv6 address into readable text. The exact signature supported by your installation depends on its PHP version and enabled extensions.

Its syntax is:

inet_ntop(string $ip): string|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 inet_ntop(inet_pton("127.0.0.1"));

Output:

127.0.0.1

Example 2: Different Input or Behavior

<?php

echo inet_ntop(inet_pton("2001:db8::1"));

Output:

2001:db8::1

Practical Example: Applying the Function

<?php

$packedAddress = inet_pton("192.0.2.15"); echo $packedAddress === false ? "Invalid" : inet_ntop($packedAddress);

Output:

192.0.2.15

Important Behavior and Edge Cases

The input must be a valid packed binary IP; check for false before converting.

Comparison With Related Functions

Common Beginner Mistakes

Key Takeaways

• Converts a packed binary IPv4 or IPv6 address into readable text.
• The input must be a valid packed binary IP; check for false before converting.
• inet_pton() converts a readable address to packed binary.

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