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DNS Lookup

A quick DNS lookup of the records that anchor a domain: its IPv4 (A) and IPv6 (AAAA) addresses, its nameservers (NS) and its zone authority (SOA). Missing or single-nameserver setups are flagged.

DNS Lookup, FAQ

What is an A record?
An A record maps a hostname to an IPv4 address. AAAA does the same for IPv6.
What are nameservers (NS)?
NS records name the authoritative DNS servers for a domain. RFC best practice is at least two, on separate networks, for redundancy.
What is an SOA record?
The Start of Authority record holds administrative data for a DNS zone: the primary nameserver, a serial number, and refresh/retry/expiry timers.

Want the complete picture? The Deliverability Radar scores a domain or IP out of 100 across DNS, authentication, reputation and connectivity, and emails you a branded PDF.

More free tools: SPF Checker · DMARC Checker · DKIM Checker · MX Lookup · Reverse DNS Lookup · MTA-STS Checker · Blocklist Checker · Blocklist Checker

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