--- title: Free A Record Lookup description: Find the IPv4 address a domain resolves to — every A record with its TTL, from the resolver of your choice. Spot a stale IP after a migration, a missing record behind a 'site can't be reached', or a round-robin set that is one address short. canonical: https://watchfor.io/a-record-lookup --- [Back to all free tools](/free-tools) # A Record Lookup Find the IPv4 address a domain resolves to — every A record with its TTL, from the resolver of your choice. Spot a stale IP after a migration, a missing record behind a 'site can't be reached', or a round-robin set that is one address short. Result No result yet Enter the inputs above and press Run. Results appear here in a moment. Monitor this 24/7 — get alerts on the first failure. [Start free](/auth/sign-up) Only run these tools against systems you own or are authorized to test. Using them to scan or probe systems without permission violates our [Terms](/legal/terms). ## What is A Record Lookup ? An A record maps a name to an IPv4 address. It is the record almost every other thing depends on: the browser resolves example.com to 93.184.216.34 before it can send a single byte, the mail server resolves the MX target's A record before it can connect, the CDN's CNAME eventually bottoms out in an A record somewhere. When it is wrong, the symptom is never "DNS is wrong" — it is "the site can't be reached", "the certificate doesn't match", or "half the users see the old server". This tool asks a resolver of your choice for the A records of any name and shows you exactly what came back — every address, its remaining TTL, the response code, and how long the lookup took. Round-robin sets show all their addresses; a name with no A record shows an empty NOERROR (the name exists, the record doesn't) or NXDOMAIN (the name doesn't exist at all), which are very different problems. ## How it works One query, answered the way your application would see it: - 1 Ask the resolver — A standard DNS query for QTYPE=A goes to the resolver you picked — a regional public one by default ( 1.1.1.1 , 8.8.8.8 , 9.9.9.9 ), or any IP you type, including an authoritative nameserver. - 2 Follow the alias if there is one — If the name is a CNAME, the resolver chases it and returns both the alias and the A records at the end of the chain. You see the chain, so a CNAME pointing at a dead name is visible rather than hidden behind an empty answer. - 3 Report the answer unmodified — Each address with the TTL the resolver has left on it, the RCODE , the resolver that answered and the elapsed time. Nothing is normalised or de-duplicated. Run it from a specific probe location when the answer depends on where you ask from — GeoDNS and anycast setups return different addresses to different regions by design. ## When you'd use it ### After changing the IP You moved to a new server or a new load balancer and updated the A record. Look it up against two or three resolvers: the ones that still return the old address are still within the old TTL. The remaining TTL on each answer tells you how long that cache has left. ### "This site can't be reached" Before touching the server, confirm the name resolves at all. NXDOMAIN means the record (or the whole zone) is missing — an expired domain, a deleted record, a typo in the zone. An address that resolves but doesn't answer is a different investigation. ### Certificate name mismatch The browser says the certificate is for another site. Often the A record points at a shared IP whose default virtual host serves someone else's certificate — the record is technically fine and practically wrong. The A lookup tells you which IP you're actually landing on. ### Verifying a round-robin set Three app servers, three A records. When one is decommissioned, its address has to leave DNS or a third of connections will fail. The lookup shows the full set as clients see it. ## Reading the result ### Multiple addresses Several A records for one name is normal — clients pick one (usually the first, and resolvers rotate the order). All of them must work; there is no health-checking in plain DNS. ### TTL The seconds the resolver will keep serving this answer before asking the authoritative server again. Low values (60–300) mean fast changes and more queries; a stale value here after a change means you are looking at a cache, not at your zone. ### NOERROR with no records The name exists (it may have other record types — a CNAME, MX or TXT) but has no A record. Common for names that only exist for email, or when only an AAAA record was published. ### Private or reserved addresses An A record pointing at 10.x , 192.168.x or 127.0.0.1 on a public name is either a leak of internal DNS into the public zone or a deliberate split-horizon setup — either way, public clients can't reach it. ## Check it yourself The same query from a terminal, against Cloudflare's resolver: dig A example.com @1.1.1.1 +noall +answer Add +trace to walk from the root servers down to the authoritative answer and bypass every cache. ## Common pitfalls ### Looking up the apex when the site lives on www example.com and www.example.com are different names with different records. A CDN setup often has a CNAME on www and an A record (or ALIAS/ANAME flattening) on the apex. Check the name users actually type. ### Trusting your own machine's answer Your laptop's resolver, a VPN, a hosts-file entry or a corporate DNS can all return something the public internet doesn't see. This tool asks from a probe on the public internet; if the two disagree, the difference is the bug. ### Expecting the change to be instant The authoritative server changes instantly; every cache in the world waits out its TTL. Lower the TTL a day before a planned move, not at the moment of it. ## Run A Record Lookup on every change, not just once. Get alerts the moment something breaks — across HTTP, DNS, SSL, RDAP, ping, blacklist and more. Free forever for 10 monitors. No card. [Start free](/auth/sign-up) ## Frequently asked questions What's the difference between an A record and an AAAA record? A holds an IPv4 address (four numbers, 93.184.216.34 ); AAAA holds an IPv6 address ( 2606:2800:220:1:248:1893:25c8:1946 ). A dual-stack host publishes both; clients with IPv6 generally prefer the AAAA record. Can an A record point to a hostname? No — an A record's value is always an IPv4 address. To point a name at another name, use a CNAME (on anything but the zone apex) or your provider's ALIAS / ANAME flattening on the apex. How many A records can one name have? As many as fit in a response, in practice dozens. Large sets are used for crude load distribution; anything that needs health checks or weights belongs in a load balancer or a managed DNS with traffic policies. Why does the IP differ from what I see in ping ? ping uses your local resolver, which may have an older cached answer, a different GeoDNS region, or a hosts-file override. Query the same resolver here to compare like with like. What TTL should I use for an A record? 300 seconds is a sensible default for anything that might move; 3600 or more for stable infrastructure to reduce query load. Lower it to 60 before a planned change and raise it again afterwards. ## Related dns tools - [DNS LookupResolve A, AAAA, MX, TXT, NS, SOA, CNAME, PTR, CAA, SRV records for any domain.](/dns-checker) - [DNS PropagationCheck how a DNS record looks from every prober region simultaneously — spot stale anycast nodes and propagation gaps on a world map.](/dns-propagation-checker) - [Whois LookupModern RDAP-based domain registration lookup: registrar, expiry, nameservers, status flags.](/whois-lookup) - [AAAA Record LookupCheck the IPv6 address a domain publishes — its AAAA records and TTLs. Confirm dual-stack is really on, catch a record that points at an address nobody listens on, and see why IPv6-only clients time out while IPv4 works.](/aaaa-record-lookup) --- Canonical page: https://watchfor.io/a-record-lookup · Site guide: https://watchfor.io/llms.txt