DNS Diagnostic

Deep-inspect any domain's DNS health — direct queries, no third-party APIs.

Checks: Delegation NS SOA MX SPF DMARC WWW
Invalid characters in domain.

What We Diagnose

7 check categories

DNS Diagnostic runs deep multi-category checks on every domain — direct queries to authoritative servers, no third-party APIs. Results arrive in real time via live streaming.

Parent Delegation
Verifies that the TLD parent zone correctly delegates to the domain's own nameservers, and detects lame or mismatched delegation.
Nameservers (NS)
Queries each authoritative nameserver directly, checking consistency, TTLs, and resolver reachability.
SOA Record
Inspects the Start of Authority record for serial number, refresh interval, retry, expire, and minimum TTL values.
MX Records
Lists mail exchange records with priority ordering and resolves each hostname to confirm mail routing is functional.
SPF & DMARC
Parses the SPF sender policy and DMARC reporting policy, flagging permissive or missing configurations.
Web & HTTP
Tests www redirect behaviour, HTTP→HTTPS upgrade, response codes, and checks for missing security headers.
CAA Records
Checks Certification Authority Authorization records to confirm which CAs are allowed to issue certificates for this domain.