How to Find a Website's IP Address

Use this when you are allow-listing an egress, confirming a cutover, or checking whether IPv6 exists. Do not use it to scan networks you do not operate, and do not type internal hostnames into a public box.

Domain to IP is the dedicated resolver. DNS Record Lookup shows the same addresses plus CNAME, MX, and TXT when the story is larger than “give me numbers.”

What “the IP” means on a modern site

Most public sites do not live on one machine under a desk. The hostname is a label. The addresses behind it are often:

• Anycast edges - many cities advertise the same IP; you hit the nearby one.
• Multiple A/AAAA records - the resolver returns a set; the client picks.
• A CNAME onto a CDN - the name you typed has no A of its own; the target does.

So the useful sentence is not “the site is 93.184.216.34.” It is “from this resolver, these addresses are currently published for this name.” Tomorrow the set can change without the company moving office.

If you need the full record mix, not just addresses, that is How DNS Records Work.

A versus AAAA, and why both matter

IPv4 is A. IPv6 is AAAA. Dual-stack hosts publish both. An IPv6-only mistake (forgotten AAAA after a rebuild, or the reverse) shows up as “works on my phone / fails on this laptop” depending on which stack the path prefers.

Domain to IP should list both families when they exist. If you only ever look at IPv4, you will miss a class of outages that Happy Eyeballs users still walk into.

A name with neither A nor AAAA, and no CNAME, is not a website yet. It may be mail-only, or a reserved label, or a typo.

CDN and anycast: one name, many answers

Resolve www of a large site from two countries and you may get different addresses. That is expected. Firewalls that pin “the” IP from a single lookup will break the next time the CDN rotates.

For allow-lists, prefer the vendor’s published IP ranges or a hostname-based allow when the product supports it. A one-shot A record is a snapshot.

Also watch the difference between apex and www. It is common for example.com and www.example.com to resolve to different places during a migration. Resolve the name users actually type, and the name your canonical tag points at.

How to resolve a public hostname

1. Strip the URL down to a hostname. https://www.example.com/path?q=1 is not a DNS name; www.example.com is.
2. Confirm you are allowed to query it. Your zone, a public site you are debugging with permission, or a vendor’s documented endpoint: yes. A private hostname on someone else’s LAN: no.
3. Open Domain to IP and submit the hostname. The tool sends that name to public DNS and returns A/AAAA.
4. If the result is empty or only a CNAME story, switch to DNS Record Lookup.
5. If you have an address and want the PTR name (mail logs, abuse), use Reverse IP Lookup. That sends the IP, not the original hostname.

Command-line equivalents (dig +short example.com A, dig AAAA) do the same class of thing: they also leave the machine. The web tool is the same contract with a simpler form.

What to do with the addresses

Firewall and NAT rules. Copy the current set, and plan for it to change. Document the hostname next to the IPs so the next person does not treat the numbers as eternal.

Comparing environments. Staging and production should not silently share an address unless you meant them to. A resolve of both names is the fastest check.

Reverse DNS. PTR is optional for websites and common for mail. A generic cloud PTR does not mean the site is “fake.” Read What Reverse DNS (PTR) Records Tell You before you over-interpret it.

TLS and HTTP. The IP is not the certificate name. Browsers validate the hostname in the certificate, not the A record. After you have addresses, SSL Certificate Checker and HTTP Header Viewer answer different questions - and they also contact the public host.

Addresses and names you should not submit

Do not put RFC1918 ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16), link-local, or loopback into a public reverse lookup and expect a useful story. Do not resolve *.internal corporate names through a public website.

If the host is yours and only reachable on a VPN, use dig against your internal resolver on a machine that is on that VPN. A public tool cannot see that view, and asking it to try is not a privacy-preserving trick - it is a failed query plus a name you should not have shipped off-network.

Resolve the hostname you are allowed to test

Open Domain to IP, enter a public hostname you are allowed to test, and read the A/AAAA set as a snapshot. If you need types beyond addresses, use DNS Record Lookup. If you already have an IPv4 address from a log line, Reverse IP Lookup is the other direction - and it sends that address on purpose.