ip2long

(PHP 4, PHP 5, PHP 7)

Converts a string containing an (IPv4) Internet Protocol dotted address into a long integer

int ip2long ( string $ip_address )

The function ip2long() generates an long integer representation of IPv4 Internet network address from its Internet standard format (dotted string) representation.

ip2long() will also work with non-complete IP addresses. Read » http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/libs/commtrf2/inet_addr.htm for more info.

Parameters:

ip_address

A standard format address.

Returns:

Returns the long integer or FALSE if ip_address is invalid.

Changelog:

5.5.0

Prior to this version, on Windows ip2long() would sometimes return a valid number even if passed a value which was not an (IPv4) Internet Protocol dotted address.

5.2.10

Prior to this version, ip2long() would sometimes return a valid number even if passed a value which was not an (IPv4) Internet Protocol dotted address.

Notes:

Because PHP's integer type is signed, and many IP addresses will result in negative integers on 32-bit architectures, you need to use the "%u" formatter of sprintf() or printf() to get the string representation of the unsigned IP address.

ip2long() will return FALSE for the IP 255.255.255.255 in PHP 5 <= 5.0.2. It was fixed in PHP 5.0.3 where it returns -1 (same as PHP 4).

Examples:

ip2long() Example

<?php
$ip = gethostbyname('www.example.com');
$out = "The following URLs are equivalent:<br />\n";
$out .= 'http://www.example.com/, http://' . $ip . '/, and http://' . sprintf("%u", ip2long($ip)) . "/<br />\n";
echo $out;
?>

Displaying an IP address

This second example shows how to print a converted address with the printf() function in both PHP 4 and PHP 5:

<?php
$ip   = gethostbyname('www.example.com');
$long = ip2long($ip);
 
if ($long == -1 || $long === FALSE) {
    echo 'Invalid IP, please try again';
} else {
    echo $ip   . "\n";           // 192.0.34.166
    echo $long . "\n";           // -1073732954
    printf("%u\n", ip2long($ip)); // 3221234342
}
?>