How to get the public IP address of the device

Question

I found this sample code to get all local IP addresses, but I don\'t find an easy solution to get the public IP.

A legacy class from Apple allowed to do that ... bu

Answer 1

I use ipify and with no complaints.

NSURL *url = [NSURL URLWithString:@"https://api.ipify.org/"];
NSString *ipAddress = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:nil];
NSLog(@"My public IP address is: %@", ipAddress);

Answer 2

I find both Andrei and Tarek's answers helpful. Both are relying a web URL to query the "public IP" of the iOS/OS X device.

However, there is an issue with this approach in some part of the world where URL such as "http://www.dyndns.org/cgi-bin/check_ip.cgi" is censored as in andrei's answer:

NSString *theIpHtml = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://www.dyndns.org/cgi-bin/check_ip.cgi"]
encoding:NSUTF8StringEncoding
                                                  error:&error];

In this case, we will need to use an "uncensored" URL within the region such as http://1212.ip138.com/ic.asp

Note that the web URL could use a different HTML and encoding than what Andrei's answer could parse - in the URL above, some very gentle changes can fix it by using kCFStringEncodingGB_18030_2000 for http://1212.ip138.com/ic.asp

NSURL* externalIPCheckURL = [NSURL URLWithString: @"http://1212.ip138.com/ic.asp"];
encoding:NSUTF8StringEncoding error:nil];

NSStringEncoding encoding = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);

NSString *theIpHtml = [NSString stringWithContentsOfURL: externalIPCheckURL
                                                   encoding: encoding
                                                      error: &error];

Answer 3

Thanks @Tarek for his answer

Here, code in Swift 4 version

func getPublicIPAddress() -> String {
    var publicIP = ""
    do {
        try publicIP = String(contentsOf: URL(string: "https://www.bluewindsolution.com/tools/getpublicip.php")!, encoding: String.Encoding.utf8)
        publicIP = publicIP.trimmingCharacters(in: CharacterSet.whitespaces)
    }
    catch {
        print("Error: \(error)")
    }
    return publicIP
}

NOTE1: To get public IP address, we must have external site to return public IP. The website I use is business company website, so, it will be their until the business gone.

NOTE2: You can made some site by yourself, however, Apple require HTTPS site to be able to use this function.