DNS Lookup & Reverse DNS Checker
Inspect DNS records, resolve an IP back to its PTR hostname, and compare public answers with the DNS used by this device, VPN, or private network.
Hostname or IP address
Device / VPN resolver setup
For private zones and split DNS, run the Bug Days bridge on this computer:
brew tap bugdays-com/holy-cors && brew install holy-cors && holy-cors docker run --rm -p 127.0.0.1:2345:2345 ghcr.io/bugdays-com/holy-cors:latest Native installs use this device’s resolver directly. Docker uses the container’s configured DNS.
See the answer each resolver sees.
Check public records immediately. Add the device resolver to diagnose VPN DNS, internal zones, split-horizon answers, and local configuration.
DNS answers
| Resolver | Type | Status | TTL | Record name | Answer | Time |
|---|
Share or take the result with you
The shared snapshot opens with these answers; it does not silently rerun the lookup.
Public DNS and the resolver on your device answer different questions
A public DNS lookup shows what an internet resolver sees. The device lookup follows the DNS configuration available to Holy CORS, which can include a VPN, a corporate DNS server, private zones, or split-horizon records. Compare them when a hostname works on one network but not another.
Reverse DNS and forward-confirmed PTR
Enter an IP address to query its PTR record. The checker also resolves returned hostnames back to A or AAAA records. A matching forward result is useful evidence of consistent DNS configuration, though it is not proof of ownership or identity.
DNS record types in this checker
Inspect A and AAAA addresses, CNAME aliases, MX mail exchangers, TXT policy and verification values, NS delegation, SOA zone data, SRV service locations, CAA certificate-authority policy, and PTR reverse mappings.