How to use it
- 1Enter a domain such as
example.comor a subdomain such asmail.example.com. You can also paste a full URL. - 2Keep “All common records” to see everything at once, or pick one record type such as MX or TXT.
- 3Click Look up. Each record type is listed with its values and TTL – how long resolvers may cache it.
- 4Enter an IP address instead to do a reverse lookup and find the hostname it belongs to.
What DNS records mean
DNS – the Domain Name System – is the internet’s address book. It turns names people remember, like example.com, into the IP addresses computers connect to, and tells mail servers where to deliver email for a domain.
A and AAAA records hold the IPv4 and IPv6 addresses of a hostname. CNAME makes one name an alias of another. MX records name the mail servers that accept email for the domain, in order of priority. NS records list the authoritative name servers, and SOA holds the zone’s administrative details.
TXT records carry text, most often SPF, DKIM and DMARC rules that protect a domain against email spoofing, and verification codes for services like Google Search Console. CAA records say which certificate authorities may issue SSL certificates for the domain.
Why a change doesn’t show up everywhere at once
Resolvers such as your provider’s DNS or 1.1.1.1 remember answers for as long as the record’s TTL (time to live) allows. After you change a record, some resolvers keep serving the old value until their cached copy expires – that delay is often called DNS propagation.
Switching the resolver between Cloudflare and Google shows whether two large public resolvers already see the same answer. Lowering the TTL a day before a planned change makes the switch faster.
Questions and answers
How do I check where a domain’s email goes?
Choose the MX record type. The records list the mail servers with their priority – the lowest number is tried first. If there are no MX records, most senders fall back to the domain’s A record.
How can I check a domain’s SPF or DMARC record?
Look up TXT records. The SPF record starts with v=spf1. For DMARC, look up the TXT records of _dmarc.yourdomain.com – the record starts with v=DMARC1.
What does NXDOMAIN mean?
NXDOMAIN means the name doesn’t exist in DNS: either it’s misspelled, the subdomain was never created, or the domain isn’t registered. Use the WHOIS tool to check whether a domain is registered.
What does “DNSSEC valid” mean?
The domain signs its DNS records cryptographically and the resolver verified the signatures, so the answers can’t have been tampered with on the way. Many domains don’t use DNSSEC yet, which is common and not an error.
Can I look up the hostname of an IP address?
Yes. Enter the IP address and the tool performs a reverse DNS lookup of its PTR record, which usually names the server or the provider that owns the address.