DNS Lookup
Query DNS records for any domain - A, AAAA, MX, NS, TXT, CNAME, SOA, and more.
What Is DNS Lookup?
DNS (Domain Name System) is the internet's phone book. It translates human-readable domain names
like example.com into machine-readable IP addresses like 93.184.216.34.
A DNS lookup queries DNS servers to retrieve these records. Every time you visit a website, send an
email, or connect to any internet service, a DNS lookup happens behind the scenes.
DNS Record Types
| Record Type | Purpose | Example |
|---|---|---|
| A | Maps a domain to an IPv4 address | example.com → 93.184.216.34 |
| AAAA | Maps a domain to an IPv6 address | example.com → 2606:2800:220:1:... |
| CNAME | Creates an alias pointing to another domain | www.example.com → example.com |
| MX | Specifies mail servers for the domain | example.com → mail.example.com (priority 10) |
| TXT | Stores arbitrary text (SPF, DKIM, domain verification) | v=spf1 include:_spf.google.com ~all |
| NS | Specifies authoritative name servers | example.com → ns1.example.com |
| SOA | Start of Authority — primary DNS info for the zone | Contains serial number, refresh intervals |
How DNS Resolution Works
- Browser Cache: The browser checks its local DNS cache first.
- OS Cache: If not found, the operating system's resolver cache is checked.
- Recursive Resolver: The query goes to your ISP's or configured DNS resolver (e.g., 8.8.8.8).
- Root Servers: The resolver queries root DNS servers to find the TLD nameserver.
- TLD Servers: The
.com(or other TLD) servers direct to the domain's authoritative nameservers. - Authoritative Server: The domain's nameserver returns the requested record.
Common Use Cases
- Domain Troubleshooting: Verify DNS records are propagated correctly after changes.
- Email Configuration: Check MX, SPF, DKIM, and DMARC records to diagnose email delivery issues.
- SSL Certificate Validation: Verify domain ownership through DNS TXT records.
- CDN Setup: Confirm CNAME records point to CDN endpoints correctly.
- Security Analysis: Inspect DNS records for unauthorized changes or misconfigurations.
How to Use This Tool
- Enter a domain name (e.g.,
example.com). - Select the DNS record type (A, AAAA, MX, CNAME, TXT, etc.).
- Click Lookup to query the DNS records.
- Review the results including TTL, record values, and nameservers.
Why Use This Tool?
- Troubleshoot DNS configuration and propagation issues.
- Verify MX records for email delivery problems.
- Check TXT records for SPF, DKIM, and domain verification.
- Essential for web administrators and DevOps engineers.
Frequently Asked Questions
What is TTL in DNS?
TTL (Time to Live) is the duration (in seconds) that a DNS record is cached by resolvers and browsers. A low TTL (e.g., 300 seconds) means changes propagate quickly but increase DNS query volume. A high TTL (e.g., 86400 seconds) reduces queries but delays propagation of changes.
How long does DNS propagation take?
DNS changes can take anywhere from a few minutes to 48 hours to propagate globally, depending on the previous TTL values and caching behavior of DNS resolvers worldwide.