DNS Lookup Tool
Inspect your domain's DNS records, understand what they mean, and troubleshoot common website, nameserver, and email configuration issues in real time.
Supported DNS Record Types
The Domain Name System uses dedicated resource record types to map internet hostnames to IP addresses, email servers, and operational verification metadata.
Address Record
Maps a hostname to an IPv4 32-bit address (e.g. 93.184.216.34). Essential for directing web browsers and clients to your IPv4 web server.
IPv6 Address Record
Maps a hostname to a 128-bit IPv6 address (e.g. 2606:2800:220:1:248:1863:25c8:1946). Required for seamless connectivity on modern IPv6 mobile networks.
Canonical Name
Aliases one domain name to another canonical hostname. Often used for subdomains pointing to CDNs, SaaS services, or cloud load balancers.
Mail Exchanger
Directs incoming email messages to authoritative mail servers, each paired with a priority number. Lower numbers designate primary mail servers.
Name Server
Delegates a DNS zone to authoritative nameservers. Identifies which DNS provider or server hosts the authoritative records for the domain.
Text Record
Holds arbitrary human or machine-readable text. Extensively used for domain ownership verification, SPF policies, DKIM keys, and DMARC rules.
Start of Authority
Specifies core administrative information about the DNS zone, including the primary nameserver, admin email, zone serial number, and refresh timers.
Certification Authority Authorization
Defines which Certificate Authorities (CAs) are permitted to issue SSL/TLS certificates for the domain, mitigating rogue certificate issuance.
How to Use the DNS Lookup Tool
Execute bounded queries and inspect real-time DNS zone data in five easy steps.
Enter Your Domain
Type your domain or subdomain (e.g. example.com). No URL schemes (https://), slashes, or account sign-in required.
Select Record Types
Choose any combination of A, AAAA, CNAME, MX, NS, TXT, SOA, or CAA records, or use one-click Default / Select All.
Execute Real-Time Query
Click 'Look Up DNS Records' to trigger parallel queries against authoritative DNS resolvers with a bounded 2-second timeout.
Inspect Values & TTLs
Review returned IP addresses, mail exchange priorities, and TTL caching durations in an organized, responsive table.
Copy & Troubleshoot
Copy individual record values or copy the complete structured text report to share with developers or hosting support.
Troubleshooting Common DNS Issues
Frequent configuration oversights and caching quirks encountered when auditing domain records.
DNS Propagation & TTL Delays
When you update DNS records at your domain registrar or DNS hosting provider, upstream recursive resolvers continue to cache previous values for the duration of the Time-To-Live (TTL) header. If your TTL is set to 86400 (24 hours), changes may take up to a full day to reflect globally.
Missing or Misconfigured MX Records
If sending mail servers cannot resolve valid MX records for your domain, inbound email will bounce. Ensure all mail exchanger hostnames point directly to A or AAAA records, rather than CNAME aliases, to comply with RFC 2181.
TXT Record Segmentation & Quotation
Long TXT entries (such as 2048-bit DKIM public keys) that exceed 255 characters must be split into multiple concatenated character-strings within the same DNS resource record. Our tool correctly reassembles string segments into their full cryptographic representation.
CNAME Flattening at Zone Apex
RFC 1034 prohibits publishing a CNAME record at the zone apex (e.g. root example.com) because it conflicts with SOA and NS records. Modern DNS providers resolve this using CNAME flattening or ALIAS records that dynamically resolve to A/AAAA records.
Limitations of DNS Lookup Tools
Understanding what a DNS lookup tool can and cannot determine about domain health and security.
Single Resolver Vantage Point
DNS results reflect the answers returned to our server-configured resolver at the exact moment of the query. Because recursive DNS servers cache records according to TTL, queries from different locations or ISPs may observe cached variations during active propagation.
Record Presence ≠ Security Score
Publishing valid DNS records does not guarantee that a website is hardened against attack. A DNS lookup reports zone pointers, but does not test SSL/TLS certificate chains, evaluate HTTP security headers, or detect web application vulnerabilities.
DNSSEC Existence vs Cryptographic Validation
While DNS queries can verify whether DNSSEC keys and signatures exist, client lookup utilities do not execute end-to-end cryptographic trust chain verification.
No Deep Subdomain Enumeration
This tool inspects the exact hostname or domain you provide. It does not perform invasive brute-force subdomain brute-forcing, zone transfers (AXFR), or unauthorized network reconnaissance.
Frequently Asked Questions
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HTTP Security Headers Checker
Audit HSTS preload readiness, Content-Security-Policy (CSP), X-Frame-Options, and referrer policies.
SPF, DKIM & DMARC Checker
Review email authentication records in DNS to protect domain reputation and prevent spoofing attacks.
HTTP Status & Redirect Checker
Inspect HTTP response status codes and trace redirect chains hop-by-hop with safe header audits.
security.txt Validator
Validate vulnerability disclosure files against RFC 9116 syntax, mandatory Contact and Expires directives.
Want to check your entire website security posture?
A DNS lookup only checks domain record pointers. Run SiteSecura's full automated perimeter scan to evaluate SSL/TLS certificates, HTTP security headers, SPF & DMARC authentication, and server fingerprints in under 30 seconds.