Built for engineers, sysadmins, and anyone who has ever stared at a SERVFAIL and wondered why.
Pick any resolver
Built-in presets for Cloudflare, Google, Quad9, OpenDNS, and AdGuard — IPv4 and IPv6. Your system resolver on macOS. Custom resolvers you define once and sync across devices.
Every transport worth having
UDP, TCP, DNS-over-TLS (853), DNS-over-HTTPS (443), and DNS-over-QUIC (853). Switch with one tap — useful when you want to see how your network treats each.
Flag-level control
Set RD (Recursion Desired), DO (DNSSEC OK), and CD (Checking Disabled) independently so you can see exactly what each bit changes in the response.
Wire bytes, colour-coded
Expand the raw-bytes view and every byte lights up by region: header, labels, compression pointers, TYPE/CLASS/TTL, RDATA. Legend right below.
Full DNSSEC chain walk
Anchor on the IANA root KSK-2017 + KSK-2024, descend through every zone cut, match DS to DNSKEY, verify each RRSIG. Every step visible with its key tag and algorithm.
Denial-of-existence proofs
NSEC and NSEC3 proofs validated in full. NXDOMAIN gets the three-part closest-encloser + next-closer + wildcard proof; NODATA gets bitmap checks; signed-parent DS-absence gets downgrade-attack protection.
Split-horizon aware
When a zone publishes both internal and external KSKs with two DS records in the parent, validation succeeds for whichever view your chosen resolver sees — no manual key juggling.
Attack detection
Enforces RFC 6840 §5.11 algorithm-downgrade protection and RFC 5011 revoked-key rules. A stripped RRSIG or retired KSK turns the step red with a specific reason, not a generic pass.
CNAME chase
Follows CNAME chains up to 10 hops, re-running the full chain walk for each target zone. No more "chain stops at CNAME" dead-ends.
Extended DNS errors
RFC 8914 reasons (DNSSEC Bogus, Signature Expired, Filtered, Blocked, …) pulled out of the OPT record and shown prominently whenever the resolver tells you why it's unhappy.
iCloud history + presets
The last 15 queries and every custom resolver you save sync across every device signed into the same Apple ID — via iCloud Key-Value storage. No accounts, no servers, no tracking.
Mac, iPhone, iPad
One universal app. Sidebar + detail split on Mac and iPad; tidy stack navigation on iPhone. All three share the same history.