How to get the ip address in Node.js Express?

Question

I am using this code to get the ip address in Node.js:

const ip = await (req.headers['x-forwarded-for'] || '').split(',').pop().trim() || req.socket.remoteAddress;

For all the devices on my home wifi network and when I access my website using data on my phone, I get this ip address: ::ffff:127.0.0.1

I'm trying to get the ip address of each individual device (phone, laptop) that visits my site. But all of the devices show the same ip address.

How do I get the individual device ip address of each device in Node.js?

EDIT:

I made some updates and no longer get ::ffff:127.0.0.1. I now get the ip address of the internet connection. So if I'm connected to wifi, I get the wifi modem ip address. If I'm using data, I get the data connection ip address.

But I need to get the device ip address. I do NOT want the connection ip address. I want the device ip address.

Here are the changes I made:

I set 'trust proxy' to true:

app.set('trust proxy', true);

I updated the etc/nginx/sites-available/mysite file to look like this:

location / {
      proxy_set_header  X-Real-IP  $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_pass http://127.0.0.1:5050;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection upgrade;
      proxy_set_header Host $host;
      proxy_cache_bypass $http_upgrade;
  }

I updated the etc/nginx/proxy_params file to look like this:

proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $remote_addr;
proxy_set_header X-Forwarded-Proto $scheme;

What did I do wrong? How do I fix this? From what I'm reading, it sounds like I should be able to use req.headers['x-forwarded-for'] to get the right ip address, but req.headers['x-forwarded-for'] returns the same thing as req.headers['x-real-ip'] except it is in an array.

While in case of routing, the IP Address is that of the router if the network is being directed through one and not of the device. Hence, you get the same IP Address for all your devices which is that of the router itself. I am not sure though but I believe this is the reason you are getting the same address. — Karan Gaur, May 31 '21 at 18:36
I thought that too at first. But the same ip address is shown when I am using my phone data, NOT my router / wifi internet. I also just asked someone and found out it shows the same ip address for a phone not on my wifi. — Page COW, May 31 '21 at 20:10
See if this helps:- https://stackoverflow.com/questions/10849687/express-js-how-to-get-remote-client-address?answertab=votes#tab-top — Karan Gaur, Jun 01 '21 at 08:26
Do you mean you want the IP address of the device on the network it is on? — CodeWalker, Jun 06 '21 at 11:56
Yes. So if my phone is connected to wifi and I access my website from my phone, I want nodejs to get the ip address of my phone, NOT the wifi connection / modem. — Page COW, Jun 06 '21 at 12:24
Might help if you stated an example what IP address you expect to get - or at least what type or range. If you're trying to get an address that's been through NAT (e.g. my machine has an address of 192.168.0.101) and you want *that* to be returned from the XFF headers for a website hosted on the public internet, then you're asking for the impossible. Same applies to any in the private ranges. See https://en.wikipedia.org/wiki/Private_network — Richard Wheeldon, Jun 06 '21 at 14:41
@RichardWheeldon So I think what I'm looking for is called the "Private Ip Address" of the device. Are you saying it is impossible to get the private ip address of a device? — Page COW, Jun 07 '21 at 10:25
What you are looking for is Local Area Network ip of your other devices. — Cerceis, Jun 08 '21 at 07:39
Yes, I'm saying it's impossible to get the Private IP address other than on the local network. If I host my own server on my own LAN, then I can see those addresses directly. No other machine on the internet outside my LAN will be able to get at it. — Richard Wheeldon, Jun 08 '21 at 12:32
I agree with Richard. you can find more info here https://stackoverflow.com/a/32841043/9964717 — Karan Gaur, Jun 08 '21 at 16:06

score 2 · Answer 1 · answered Jun 08 '21 at 07:42

What you could be looking for is Local Area Network Ip address:
You could use default function by Node.js os.networkInterfaces()

You could find the documentation here:
https://nodejs.org/api/os.html#os_os_networkinterfaces

You could also look into this thread:
Get local IP address in Node.js

score 1 · Accepted Answer · answered Jun 09 '21 at 10:36

I found another solution for my use case. Based on some people's comments, it looks like it may not be possible to find the private ip address of a device that connects to your website, only the public ip address.

@Cerceis os.networkInterfaces() answer may work. I did a quick test, but was unable to know for sure if it works. I don't have time to test it out more fully. If you are hoping to find an answer, I would try out os.networkInterfaces() in Node.js and that might get you the ip address you're looking for.

score 0 · Answer 3 · answered Jun 13 '21 at 10:54

You can use the Native os module in Node.js. It provides all the operating system-related utility methods and properties.

var os = require('os');
var allNetworkInterfaces = os.networkInterfaces();
console.log(allNetworkInterfaces);

The call to os.networkInterfaces() will return an object containing network interfaces that have been assigned a network address. The output of the above code looks like this:

{
  lo: [
    {
      address: '127.0.0.1',
      netmask: '255.0.0.0',
      family: 'IPv4',
      mac: '00:00:00:00:00:00',
      internal: true,
      cidr: '127.0.0.1/8'
    },
    {
      address: '::1',
      netmask: 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff',
      family: 'IPv6',
      mac: '00:00:00:00:00:00',
      scopeid: 0,
      internal: true,
      cidr: '::1/128'
    }
  ],
  eth0: [
    {
      address: '192.168.1.108',
      netmask: '255.255.255.0',
      family: 'IPv4',
      mac: '01:02:03:0a:0b:0c',
      internal: false,
      cidr: '192.168.1.108/24'
    },
    {
      address: 'fe80::a00:27ff:fe4e:66a1',
      netmask: 'ffff:ffff:ffff:ffff::',
      family: 'IPv6',
      mac: '01:02:03:0a:0b:0c',
      scopeid: 1,
      internal: false,
      cidr: 'fe80::a00:27ff:fe4e:66a1/64'
    }
  ]
}

score -1 · Answer 4 · answered Jun 09 '21 at 01:33

Finding the IP address is Node.js

One of the easiest methods of finding the IP address is to use the "ip" NPM module. It is super quick and easy (and it has worked for me in the past)

const ip = require('ip')
console.log(ip.address())

Learn more at: https://www.npmjs.com/package/ip

How to get the ip address in Node.js Express?

4 Answers4

Finding the IP address is Node.js