Looking up DNS records...
Enter a domain or IP address and choose a record type to query public DNS records.
What Is DNS and Why Does It Matter?
The Domain Name System (DNS) is the phonebook of the internet. Every website, email server, and API endpoint relies on DNS to translate human-friendly domain names like example.com into machine-friendly IP addresses. Without DNS, users would have to memorize strings of numbers to reach any online service.
When you type a domain into a browser, your device asks a DNS resolver a series of questions: What is the IPv4 address? Is there an IPv6 address? Where should email be delivered? Are there verification text strings? Each answer is stored in a different DNS record type, and together they define how traffic reaches and trusts your domain.
IT administrators and website owners check DNS records daily to troubleshoot outages, verify email configuration, migrate hosting providers, and confirm that security records like SPF, DKIM, and DMARC are published correctly.
Common DNS Record Types Explained
Understanding the most common record types helps you diagnose domain issues faster and communicate clearly with hosting or email providers.
| Type | Purpose | Typical Use Case |
|---|---|---|
| A | Maps a domain to an IPv4 address | Pointing a website to a web server |
| AAAA | Maps a domain to an IPv6 address | Modern IPv6-enabled services |
| CNAME | Creates an alias to another domain | Redirecting www to apex domain |
| MX | Defines mail servers and priority | Receiving email at a custom domain |
| NS | Lists authoritative name servers | Showing who manages DNS |
| TXT | Publishes arbitrary text strings | SPF, DKIM, DMARC, domain verification |
| PTR | Reverse IP to hostname mapping | Email deliverability and security checks |
How This DNS Lookup Tool Works
Our DNS lookup tool queries public DNS resolvers directly from the server using Go's standard networking library. When you enter a domain and select a record type, the tool asks the resolver for the matching records, sorts them for readability, and displays them in a clean table.
The ALL option runs multiple queries in parallel and merges the results so you can see the full DNS picture for a domain in one view. The PTR option works in reverse: you provide an IP address, and the tool returns any hostname mappings associated with it.
Please note that this tool does not display TTL (time-to-live) values because Go's standard resolver API does not expose them. TTL tells resolvers how long to cache a record before asking again. If you need TTL data, use a command-line tool like dig or nslookup with a specific name server.
Frequently Asked Questions
What is the difference between A and AAAA records?
A records return IPv4 addresses like 192.0.2.1, while AAAA records return IPv6 addresses like 2001:db8::1. Most modern networks support both, but IPv6 is increasingly important as IPv4 addresses become scarce.
Why does my domain have multiple MX records?
Multiple MX records provide redundancy. Each MX record includes a priority value — lower numbers are preferred. If the primary mail server is unreachable, email senders automatically try the next server in the list.
What are TXT records used for?
TXT records publish plain-text information publicly. They are commonly used for email authentication (SPF, DKIM, DMARC), domain ownership verification for Google Search Console or Microsoft 365, and security policies.
Why is reverse DNS (PTR) important?
Reverse DNS maps an IP address back to a hostname. Email servers often reject messages from IPs without matching PTR records because it suggests the sender may not be legitimate. PTR is also useful for network troubleshooting and security forensics.
Why can DNS lookup results differ by location?
DNS uses distributed caches across the internet. A record change may be visible immediately in one region but delayed in another until TTLs expire. Authoritative name servers always show the latest data, but recursive resolvers may serve cached responses.
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