DNS Lookup

Check DNS records online for any domain — A, AAAA, MX, NS, TXT, CNAME, SOA. Free DNS lookup tool with instant nslookup results, TTL values, and authoritative server data.

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APIPOST /api/v1/dns/lookup
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Try also: SSL Checker
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Key Features

100% Free

No registration required, unlimited checks

Instant Results

Real-time analysis with detailed output

REST API Access

Integrate into your workflow via API

Accurate Data

Live queries to authoritative sources

What is DNS Lookup?

A DNS lookup queries the Domain Name System to find all records associated with a domain name. When you enter a domain like example.com, the tool sends queries to authoritative DNS servers and returns the complete set of records: A records (IPv4 addresses), AAAA records (IPv6 addresses), MX records (mail servers and priorities), NS records (nameservers), TXT records (SPF, DKIM, DMARC, domain verification strings), CNAME records (aliases), and SOA records (zone authority data). Each record includes TTL (time to live) values that control how long DNS resolvers cache the data.

This free online DNS checker is essential for system administrators troubleshooting DNS resolution issues, web developers verifying domain configuration after migration, SEO specialists checking DNS propagation, and email administrators diagnosing mail delivery problems. Unlike command-line tools like nslookup or dig, this DNS lookup tool runs directly in your browser with no installation required and presents results in a clear, structured format.

How to Use

  1. 1Enter the domain name you want to look up (e.g., example.com — no need to include http:// or www)
  2. 2Click 'Run Check' to send DNS queries to authoritative nameservers
  3. 3Review all returned records — the results are grouped by record type (A, AAAA, MX, NS, TXT, CNAME, SOA)
  4. 4Check TTL values for each record to understand caching behavior and propagation timing
  5. 5Use the results to diagnose issues: missing A records mean the domain won't resolve, missing MX records mean email won't work, missing TXT records can cause SPF/DKIM failures
  6. 6Share the results link with your team for collaborative troubleshooting

Who Uses This

System Administrators

Monitor and troubleshoot infrastructure

Developers

Debug network issues and integrate via API

SEO Specialists

Verify domain configuration and performance

Security Analysts

Audit and assess network security

Frequently Asked Questions

What is a DNS lookup and how does it work?
A DNS lookup is the process of querying the Domain Name System to retrieve records associated with a domain name. When you type a domain into the tool, it contacts the authoritative DNS servers responsible for that domain and requests all available records. The DNS acts like a phone book for the internet — it translates human-readable domain names (like example.com) into IP addresses (like 93.184.216.34) that computers use to communicate. A full DNS lookup returns not just IP addresses but also mail server configurations, nameserver assignments, text records used for email authentication, and zone authority data.
How do I check DNS records for a domain?
Enter the domain name in the input field and click Run Check. The tool queries authoritative DNS servers and displays all available records including A, AAAA, MX, NS, TXT, CNAME, and SOA records with their TTL values. You don't need to install any software — this free DNS lookup tool works directly in your browser. For best results, enter just the domain (example.com) without http:// or www prefixes. To check a specific subdomain, enter it fully (e.g., mail.example.com or blog.example.com).
What DNS record types can I look up?
You can look up all standard DNS record types: A records map a domain to an IPv4 address, AAAA records map to IPv6 addresses, MX records define mail servers and their priorities for email delivery, NS records identify the authoritative nameservers for the domain, TXT records store text data like SPF policies, DKIM keys, and domain verification tokens, CNAME records create aliases pointing one domain to another, and SOA records contain zone administration data including the primary nameserver, admin email, and refresh intervals.
What is the difference between DNS lookup and nslookup?
Nslookup is a command-line tool built into most operating systems that queries DNS servers for specific record types. A DNS lookup tool like this one performs the same function but through a web interface — no terminal knowledge or software installation required. This online DNS checker also queries all record types at once and presents them in a structured, easy-to-read format, whereas nslookup typically requires separate queries for each record type. Both tools query the same DNS infrastructure and return the same data.
Why are my DNS records not showing the correct values?
If your DNS records appear incorrect or outdated, the most likely cause is DNS caching. After changing DNS records, it can take up to 48 hours for the changes to propagate across all DNS servers worldwide. The propagation time depends on the TTL value of the previous record — if it was set to 86400 seconds (24 hours), resolvers will cache the old value for up to that duration. You can use our DNS Propagation tool to check which servers have updated and which still serve cached data. If records are missing entirely, verify your configuration at your DNS provider's dashboard.
How do I find the A record for a domain?
Enter the domain name in the DNS lookup tool and run the check. The A record will appear in the results showing the IPv4 address the domain resolves to. If a domain has multiple A records (common for load-balanced websites), all addresses will be listed. If no A record exists, the domain won't resolve to an IPv4 address — this could mean the domain uses only AAAA (IPv6) records or that DNS is not configured for web hosting.
Can I use DNS lookup to check MX records for email troubleshooting?
Yes — MX record lookup is one of the most common uses of DNS checking. The tool displays all MX records for a domain with their priority values (lower numbers mean higher priority). If email isn't being delivered to a domain, missing or misconfigured MX records are often the cause. Check that MX records point to valid, reachable mail servers and that priority values are set correctly. For domains using Google Workspace, Microsoft 365, or other email providers, the MX records should match the values provided by your email service.

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API Endpoint

POST /api/v1/dns/lookup
View Documentation