WP_Http::is_ip_address() │ public static │ WP 3.7.0

Determines if a specified string represents an IP address or not.

This function also detects the type of the IP address, returning either '4' or '6' to represent an IPv4 and IPv6 address respectively. This does not verify if the IP is a valid IP, only that it appears to be an IP address.

Method of the class: WP_Http{}

No Hooks.

Return

Int|false. Upon success, '4' or '6' to represent an IPv4 or IPv6 address, false upon failure.

Usage

$result = WP_Http::is_ip_address( $maybe_ip );
$maybe_ip(string) (required)
A suspected IP address.

Changelog

Since 3.7.0 Introduced.

WP_Http::is_ip_address() code WP 6.6.2

wp-includes/class-wp-http.php 
public static function is_ip_address( $maybe_ip ) {
	if ( preg_match( '/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/', $maybe_ip ) ) {
		return 4;
	}

	if ( str_contains( $maybe_ip, ':' ) && preg_match( '/^(((?=.*(::))(?!.*\3.+\3))\3?|([\dA-F]{1,4}(\3|:\b|$)|\2))(?4){5}((?4){2}|(((2[0-4]|1\d|[1-9])?\d|25[0-5])\.?\b){4})$/i', trim( $maybe_ip, ' []' ) ) ) {
		return 6;
	}

	return false;
}