Need to check DNS records for a domain right now? Our free online DNS lookup tool returns A, AAAA, MX, TXT, CNAME, and NS records instantly — no terminal, no signup, no install.
Enter any domain and select the record type you want to check. Results come back in seconds from live DNS resolvers, so you're always seeing the current published state — not a cached copy from your local machine.
DNS (Domain Name System) is the distributed directory that maps human-readable domain names to machine-usable addresses and routing information. Every domain you own has a set of DNS records published in the global DNS, and every internet-connected service — mail servers, web servers, CDNs, identity providers — depends on those records being correct.
You need to look up DNS records in three broad scenarios:
A new subdomain isn't resolving. Email is bouncing. An SSL certificate can't be issued because the ACME challenge TXT record isn't appearing. In all these cases, the first step is to check what DNS is actually returning — not what you think you configured.
You moved a site to a new server and updated the A record. You transferred a domain to a new registrar. You switched to a new email provider and updated the MX records. DNS changes take time to propagate — typically minutes to a few hours, sometimes up to 48 hours. A DNS lookup tool lets you verify that the new record values are visible globally before you consider the migration complete.
Email authentication depends entirely on DNS records. SPF is a TXT record. DKIM is a TXT record at a specific selector subdomain. DMARC is a TXT record at _dmarc.yourdomain.com. If any of these are missing or malformed, outbound email from your domain will be marked as spam or rejected outright. Looking them up by record type is the fastest way to confirm they're published correctly.
| Record type | Purpose | Common use case |
|---|---|---|
| A | Maps domain → IPv4 address | Point domain to web server |
| AAAA | Maps domain → IPv6 address | IPv6-enabled hosting |
| CNAME | Alias one domain to another | www → root domain; CDN configuration |
| MX | Mail server routing | Direct email to Gmail, Fastmail, your mail server |
| TXT | Arbitrary text data | SPF, DKIM, DMARC, domain ownership verification |
| NS | Authoritative nameservers for a zone | Verify which nameservers control a domain |
| SOA | Start of authority — zone metadata | Debugging zone delegation issues |
For most day-to-day debugging, you'll be looking at A, CNAME, MX, and TXT records. NS records are useful when you've transferred a domain and need to confirm the nameserver delegation is correct.
Both approaches are useful. Here's when each makes sense:
Use this when you want to see what DNS resolves to from an external perspective — not from your local machine. Local DNS caches can hold stale records for hours. Your ISP's resolver may not have picked up a recent change yet. Our tool queries authoritative resolvers directly, so you get the current global view.
It's also the right choice when you're not at a terminal: checking from a phone, sharing a result with a non-technical colleague, or just want a clean readable output.
Use dig, nslookup, or host when you need full control: specifying a particular resolver, tracing delegation, or scripting lookups in a CI pipeline.
# Check A records using Google's resolver
dig A example.com @8.8.8.8
# Check MX records
dig MX example.com
# Check TXT records (useful for SPF/DKIM)
dig TXT example.com
# Trace the full delegation chain
dig +trace example.comCheck NS records first. If the NS lookup returns NXDOMAIN or no records, the domain's nameserver delegation is broken — either the domain has expired, the registrar configuration is wrong, or the nameservers listed are not actually authoritative.
This is almost always a DNS propagation issue. After updating an A or CNAME record, different resolvers around the world will pick up the change at different times, depending on the previous TTL of the old record. Check the record from multiple resolvers to confirm the new value is spreading.
If mail is bouncing or being marked as spam, check your MX records first (are they pointing to the right mail server?), then your TXT records (is SPF published? does DKIM have the right selector?). Many email providers give you specific record values to add — the lookup tool lets you confirm they're in DNS correctly.
ACME DNS challenges require a specific TXT record at _acme-challenge.yourdomain.com. If the challenge fails, use the DNS lookup tool to check whether the TXT record is actually present and has the right value before retrying the certificate issuance.
When you run a lookup for a domain's A record and get back one or more IP addresses, you're seeing the current authoritative answer. Multiple IP addresses for the same domain usually mean the server operator is using round-robin DNS for basic load distribution.
For MX records, the result includes a priority number (lower is higher priority). Mail servers try the lowest-priority MX first and fall back to higher numbers if it's unavailable. A typical Google Workspace MX setup looks like:
priority: 1 → aspmx.l.google.com
priority: 5 → alt1.aspmx.l.google.com
priority: 5 → alt2.aspmx.l.google.com
priority: 10 → alt3.aspmx.l.google.com
priority: 10 → alt4.aspmx.l.google.comFor TXT records, SPF records start with v=spf1. DMARC records start with v=DMARC1. If you see neither, those records aren't published yet.
DNSWatch monitors your domain's DNS records and alerts you the moment something unexpected changes — a record is modified, removed, or an MX configuration shifts. Catch unauthorized changes and misconfigurations before they cause downtime.
Join the DNSWatch waitlist → Run a DNS lookup (free)