Free A Record & AAAA Record Checker — Lookup IPv4 & IPv6 DNS Records
Instantly check any domain's A and AAAA records. Verify IPv4 and IPv6 address assignments for email deliverability, website routing, and DNS infrastructure health.
Why A & AAAA Records Matter for Email
What This A Record Checker Returns
We perform a live DNS lookup and return all A and AAAA records registered for your domain.
Common A Record Use Cases
A records are the most fundamental DNS record type. Here is when verifying them matters most.
Hosting migration — confirm new server IP is live in DNS before pointing traffic
Email server setup — verify your MX host resolves to a valid IP for deliverability
SPF alignment — cross-check that your sending IP matches your A record
IPv6 readiness — confirm AAAA records exist for dual-stack delivery
Post-propagation check — verify A records updated correctly after TTL expiration
Security audit — detect unexpected IP assignments on sensitive subdomains
How to Read A Record Results
Understanding the result helps you take the right action for your domain configuration.
Check IPv4 Addresses
A records show every IPv4 address your domain currently resolves to. Multiple A records are common for load-balanced servers. Confirm they match your expected hosting provider.
Verify IPv6 Addresses
AAAA records show IPv6 addresses. Many modern email servers require IPv6 support. Missing AAAA records can prevent delivery from IPv6-only infrastructure.
Not Found Is Normal for Some Subdomains
If a subdomain shows No A Record, it may use a CNAME alias instead. Root domains typically always have A records — a missing root A record indicates a misconfiguration.
Error Means Resolution Failed
Check domain spelling and confirm it exists in your DNS registrar. Recent changes may not have propagated — TTL times range from 5 minutes to 48 hours.
Who Uses A Record Lookup
A record checking is standard practice across hosting, email, DevOps, and security workflows.
System administrators verifying server IP assignments after migration
Email engineers checking MX host resolution for deliverability
DevOps teams confirming DNS changes propagated after updates
Security analysts auditing IP assignments on sensitive subdomains
Web developers checking domain-to-IP mapping for custom domains
Frequently Asked Questions
What is an A record?
An A record maps a domain name to an IPv4 address. It is the most fundamental DNS record type — without it, DNS cannot resolve your domain to a server.
What is an AAAA record?
An AAAA record maps a domain name to an IPv6 address. As the internet migrates to IPv6, email servers and web infrastructure increasingly require AAAA records for dual-stack connectivity.
Why does my email domain need an A record?
SPF validation, anti-spam systems, and DMARC verification all rely on DNS resolution. If your email-sending domain or MX host lacks an A record, receiving servers cannot verify your identity, which leads to rejection or spam folder placement.
Can a domain have multiple A records?
Yes. Multiple A records are common for load-balanced servers — each record points to a different IP, and DNS resolvers cycle through them. This is called round-robin DNS.
What does 'No A record found' mean?
It means no A record exists for the queried hostname at the current TTL. The domain may use a CNAME alias instead, or the record may not yet have propagated after a recent DNS change.
How long does A record propagation take?
With a TTL of 300 seconds (5 minutes), most resolvers see the new A record within 15 minutes. Legacy TTL values of 3600 to 86400 seconds can take 1 to 48 hours to propagate globally.
Does this tool show both IPv4 and IPv6 records?
Yes. The tool returns all A records (IPv4) and AAAA records (IPv6) registered for the domain in a single lookup.
Does this tool store the domains I check?
No. All DNS lookups are performed in real time without retaining any domain data after the query completes.