How to get ip address of any website using JS & nodejs? Code Example

Nodejs provides node:dns module which can be used to fetch DNS information of any website or host. In this article we will check out a code example to get ip address of any website using JS and node.

There are various methods in this module which returns information like –

• Website IP Addresses
• Family of IP like IPV4 or IPV6
• Port number like 80 or 8888
• Nameserver
• Hostmaster
• Priority
• TTL
• Type of record like A, AAAA, CNAME, MX, TXT etc.

Code Example

1. Using dns.lookup for single IP address

const dns = require('node:dns');

dns.lookup('nodejs.org', (err, address, family) => {
  console.log('address: %j family: IPv%s', address, family);
});

The output is –

address: "104.20.22.46" family: IPv4

But nodejs is running on multiple ip addresses and dns.lookup gave only one. If you want to get the list of all the ip addresses then use dns.resolve4.

2. Using dns.resolve4 for ip address list

const dns = require('node:dns');

dns.resolve4('nodejs.org', (err, addresses) => {
  if (err) throw err;

  console.log(`addresses: ${JSON.stringify(addresses)}`);
});

The output is –

addresses: ["104.20.22.46","104.20.23.46"]

3. Reverse lookup of host from ip address

If you want to get the host name from ip address then you can use dns.reverse function which accepts an ip address and returns the host name. Check this code –

const dns = require('node:dns');
const ipAddress = '207.241.224.2' // IP of archive.org

dns.reverse(ipAddress, (err, hostnames) => {
    if (err) {
      throw err;
    }
    console.log(`reverse for ${ipAddress}: ${JSON.stringify(hostnames)}`);
});

Output is –

reverse for 207.241.224.2: ["www.archive.org"]

4. Indepth DNS information

If you want to get information like nameservers, hostmaster, family, ttl, priority etc. you can use dns.resolveAny function. Check this code example –

const dns = require('node:dns');

dns.resolveAny('nodejs.org', (err, ret) => {
    if (err) {
      throw err;
    }
    console.log(`All records: ${JSON.stringify(ret)}`);
});

Errors in DNS lookup

DNS lookup is not always successful. This is because of timeouts and restrictions from viewing the records by hosts. In this section we will see all the different kinds of errors you can get –

Error Code	Details
NODATA	When server returns no data
FORMERR	Formatting error
SERVFAIL	Some general failure
NOTFOUND	Domain name not found
NOTIMP	Not implemented
REFUSED	Refused to process
BADQUERY	Query is not right
BADNAME	Host name is wrong
BADFAMILY	Address family is wrong
BADRESP	Response is wrong
CONNREFUSED	Could not contact DNS server
TIMEOUT	Timeout while processing
EOF	End of file
FILE	File processing error
NOMEM	No memory available
DESTRUCTION	Channel is destroyed
BADSTR	Bad string
BADFLAGS	Illegal flags
NONAME	Not a valid host name
BADHINTS	hints flags are invalid
NOTINITIALIZED	library not initialized
LOADIPHLPAPI	Error loading iphlpapi.dll
ADDRGETNETWORKPARAMS	Could not find GetNetworkParams function
CANCELLED	DNS query cancelled