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Free DNS Lookup Tool

Check every DNS record for any domain across three public resolvers at once, or enter an IP for a reverse lookup. No sign-up required.

How to run a DNS lookup in 3 steps

This DNS lookup online tool returns every common record type in a single query, and shows you what three independent resolvers each think the answer is.

1. Enter a domain or an IP

Type any domain to see its records. Enter an IP address instead and the tool runs a reverse DNS lookup, returning the hostname that address points back to.

2. Get every record type at once

A, AAAA, MX, TXT, NS, CNAME and SOA all in one query. Most tools make you pick a type and run a separate lookup for each one.

3. Compare across three resolvers

Every record is queried against Google, Cloudflare and Quad9 at the same time. When they disagree, a change is still propagating, and the tool says so.

What each DNS record type does

A full DNS records lookup returns several different record types, each doing a distinct job:

A and AAAA. Point the domain at an IPv4 and an IPv6 address respectively. This is what makes the website load.
MX. Where email for the domain should be delivered, with a priority number deciding the order servers are tried. An MX lookup is the first thing to run when mail stops arriving.
TXT. Free-form text, in practice carrying SPF, DKIM and DMARC policies plus domain verification strings. A DNS TXT lookup is how you confirm your email authentication is actually published.
NS. The nameservers authoritative for the domain. If you edited records somewhere that is not listed here, your changes will never take effect.
CNAME. An alias pointing one name at another. A CNAME lookup on www usually shows it pointing at the root domain.
SOA.The zone's administrative record, carrying the serial number that increments on every change.

Using it as a DNS propagation lookup

Every record here is queried against Google, Cloudflare and Quad9 at the same time. That is the point of the comparison: DNS changes do not take effect everywhere at once, because resolvers cache the previous answer until its TTL expires. If all three agree, your change has landed at least across those three networks. If they disagree, it is still in flight, and the tool flags the record.

Being straight about the limit: three resolvers is a useful signal, not a global propagation map. Dedicated propagation checkers query dozens of servers around the world and will give you a more complete picture across regions. What three well-chosen resolvers do tell you reliably is whether a change has started propagating at all, and whether the problem is propagation or something local to your own machine.

That last distinction is the one that saves time. If all three public resolvers return your new record and your browser still does not, the DNS is fine and your own cache is stale.

One caveat on reading a disagreement. Some large domains run DNS across two providers for redundancy, so different resolvers reach different authoritative servers and the SOA record differs permanently rather than temporarily. GitHub is a live example, served by both NS1 and Route 53. A and AAAA records are excluded from the comparison for the same reason: GeoDNS returns a different address to each resolver by design.

Reverse DNS lookup by IP address

Enter an IP address rather than a domain and the tool switches to a reverse DNS lookup, querying the PTR record to find the hostname that address resolves back to. It is the same tool, no separate page needed.

Reverse DNS matters most for email deliverability. Receiving mail servers commonly check that a connecting IP has a valid PTR record, and treat mail from an address without one as more likely to be spam. If you run your own mail server, missing reverse DNS is one of the first things to fix. Plenty of IP addresses have no PTR record at all, which is normal rather than an error.

Frequently asked questions

How can I check DNS records online?

Enter the domain in the tool above and it returns every common record type at once. It queries Google, Cloudflare and Quad9 public resolvers directly rather than relying on one, so you see not just the records but whether the three agree on them. No account is needed and there is nothing to install.

Where can I find DNS records?

They live on the nameservers listed in your NS record, which is usually whoever you bought the domain from or whoever hosts your DNS, such as Cloudflare, Route 53 or your registrar. To edit them you go to that provider's dashboard. To simply read them, any DNS lookup tool including this one will do, since DNS is public by design.

Which DNS records do I need?

At minimum an A record, so the domain resolves to your web server, and NS records, which your registrar sets. If you send or receive email you need MX records, plus TXT records for SPF and DKIM, and increasingly a DMARC record too. AAAA is worth adding for IPv6. CNAME is for aliases such as pointing www at the root domain.

What is DNS with an example?

DNS is the system that turns a name people can remember into an address machines can route to. When you type example.com, your computer asks a DNS resolver for that domain's A record, gets back something like 93.184.216.34, and connects to that address. Without DNS every site would have to be reached by its raw IP.

Can you give me an example of a DNS A record?

An A record maps a hostname to an IPv4 address, so it looks like example.com pointing to 93.184.216.34. A domain can have several A records returning different addresses, which is how sites spread traffic across multiple servers. The AAAA record does the same job for IPv6 addresses, which is why you often see both.

What does an MX record tell you?

An MX record says which mail servers accept email for a domain, and in what order to try them. Each record carries a priority number, and lower numbers are tried first. So an MX lookup returning 10 smtp.google.com means mail for that domain goes to Google. If a domain has no MX records it cannot receive email at all.

What is the difference between an A record and an MX record?

An A record points the domain at a web server, an MX record points its email at a mail server, and they are usually different machines entirely. This trips people up regularly: your website can be on one host while your email runs through Google Workspace or Microsoft 365, and the two are configured independently. Breaking one does not necessarily break the other.

Where can I get my MX record?

Run an MX lookup on your domain in the tool above and you will see exactly what the public internet sees. To change them, log in to whoever runs your DNS, which is the provider named in your NS records. If you are setting up email with a provider like Google or Microsoft, they will give you the exact MX values to enter.

What does reverse DNS lookup do?

A reverse DNS lookup goes the other way: you give it an IP address and it returns the hostname that address is registered to, using a PTR record. It matters most for email, because receiving mail servers routinely check that a sending IP has valid reverse DNS and will treat mail from an address without it as more likely to be spam.

Is there a free reverse DNS service available?

Yes, this one. Enter an IP address instead of a domain in the tool above and it performs the reverse lookup automatically, no account required. Note that many IP addresses have no PTR record set at all, which is not an error, it simply means the owner never configured one.

How do I perform a reverse DNS lookup on Windows?

Open Command Prompt or PowerShell and run nslookup followed by the IP address, for example nslookup 8.8.8.8. On macOS or Linux the equivalent is dig -x 8.8.8.8 or host 8.8.8.8. The tool above is nslookup online in effect: it does the same job without needing a terminal, and checks three resolvers rather than only the one your machine happens to use.

How to trace a DNS lookup?

To see the full resolution path from the root servers downward, use dig +trace example.com on macOS or Linux. That shows each step of the delegation chain. This tool does not trace the hierarchy, it queries three independent public resolvers and compares their answers, which is the more practical check when you are debugging a change that has not taken effect everywhere yet.

How long does DNS propagation take?

Usually minutes to a few hours, and up to 48 hours in the worst case. The controlling factor is the TTL on the record before you changed it, since resolvers cache the old answer for that long. Lowering the TTL a day before a planned change is the standard trick for making the switch fast.

Why isn't my DNS propagating?

The usual causes, in order of likelihood: the old record is still cached and its TTL has not expired; you edited records at a provider that is not actually authoritative for the domain, which happens when NS records point elsewhere; or your own machine or router is caching the old answer. Comparing three resolvers as this tool does separates a genuine propagation delay from purely local caching.

How to speed up DNS propagation?

You cannot force other people's resolvers to drop a cached record, so the honest answer is that you mostly cannot. What you can do is lower the TTL well before making the change, so caches expire quickly when it happens. Locally you can flush your own DNS cache, but that only affects your machine, not the visitors you actually care about.

How do I check my DNS history?

You cannot, at least not from DNS itself. DNS only ever serves the current answer, with no record of what came before, so no lookup tool can show you history. Commercial services build historical databases by polling domains repeatedly over time, and that is the only way to get it. This tool shows you what the three resolvers return right now.

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