DNS Lookup

How to use DNS Lookup

What it does & when you need it

DNS Lookup queries the public Domain Name System for a hostname and shows you the raw records behind it: the IP addresses a name resolves to, the mail servers that accept its email, the text records that prove domain ownership, and more. Reach for it when a site "works for me but not for them," when email is silently landing in spam, when you've just changed a provider and are waiting for a record to go live, or when you simply want to see who a domain points at without installing dig or nslookup.

Unlike most tools on Devtools, this one is not purely client-side. Browsers can't open raw DNS sockets, so the lookup runs on our server: the domain you type and the record type you pick are sent to our API, which asks a resolver and sends the answer back. Nothing is stored, but be aware the query does leave your device — don't treat an internal-only hostname as secret when you look it up here.

How to use

1. Type a domain into the Domain field (for example example.com). Enter the bare hostname, not a full URL — drop the https:// and any path.
2. Pick a Record type. A (IPv4) is the default; switch to MX to inspect mail routing, TXT for SPF/DKIM and verification strings, NS for the authoritative name servers, AAAA for IPv6, CNAME for aliases, or SOA for the zone's administrative record.
3. Press Look up (or Ctrl/Cmd + Enter). Results appear in a card: address and name records list one value per line, MX records show each mail exchange with its priority, and SOA is rendered as formatted JSON. An empty answer reads "No records found."

Things worth knowing

Every record type answers a different question. A and AAAA map a name to an IPv4 or IPv6 address; MX points to mail servers and carries a priority where the lowest number is tried first; TXT holds arbitrary text such as SPF policies, DKIM keys, and domain-verification tokens; NS names the authoritative servers for the zone; CNAME declares that one name is an alias of another; and SOA is the zone's "start of authority" — the primary server, admin contact, and refresh timers. Choosing the right type is half of a good diagnosis.

TTL is why DNS feels slow. Every record ships with a time to live, a number of seconds that resolvers are allowed to cache the answer. When you change a record, the world can keep serving the old value until that TTL expires — which is exactly why an update you made an hour ago still hasn't "propagated." If you're about to migrate, lower the TTL a day in advance so the cutover is quick.

This lookup runs from our resolver, not your machine. The answer reflects what our server sees, which may differ from your own network. Providers commonly use geo-based or split-horizon DNS to hand different IPs to different regions, and a corporate network may resolve internal names that the public internet never sees. If a value here disagrees with your laptop, that's often the reason — compare it against What's My IP and your local dig output.

TXT records are where mail deliverability breaks. SPF and DKIM both live in TXT, and a single typo — a missing include:, a stray character in a DKIM key — can quietly route your mail straight to spam without any bounce. Checking TXT here is a fast first diagnostic before you go deeper. From there, pair this with the SSL Checker to confirm the certificate matches, and the HTTP Headers tool to see how the resolved host actually responds.