About IP DNS Hub

IP DNS Hub is a free, professional-grade network diagnostics platform built for developers, sysadmins and DNS engineers. It consolidates the most commonly used DNS and IP tools into a single, fast interface — no account required.

The Domain Name System

DNS is the internet's distributed address book, translating human-readable hostnames into machine-routable IP addresses. Despite its seemingly simple job, DNS configuration is notoriously complex: a single misconfigured SOA serial, a missing glue record or a broken MX chain can silently break email delivery, slow down page loads or prevent a domain from resolving entirely across parts of the world.

The protocol is defined primarily in RFC 1034 and RFC 1035, with dozens of later extensions covering DNSSEC, EDNS, AXFR, IXFR and more. This tool was built on years of experience diagnosing real-world DNS failures, and it is continuously updated as new failure patterns emerge.

How IP DNS Hub Works

DNS Report

The flagship tool runs approximately 20 automated checks modelled after RFC best practices and real-world postmaster experience. It queries your domain at four levels: parent zone delegation, authoritative nameserver consistency, SOA record validity, MX reachability and WWW resolution. Each check is categorised as Pass, Warning or Error, with an explanation of why it matters and what to fix.

Reverse Lookup Engine

Unlike tools that rely on third-party APIs with rate limits, IP DNS Hub builds its own reverse lookup database. Every DNS query run on this site automatically extracts and stores the resolved A, NS and MX records. The same domain queried twice updates a LastSeen timestamp; a domain migrating to a new IP inserts a new row, preserving the history. Over time this builds an organic, first-party dataset that powers Reverse IP, Reverse NS, Reverse MX and IP History lookups without hitting external quotas.

DNS Propagation Checker

Simultaneously queries seven globally distributed public resolvers (Google, Cloudflare, Quad9, OpenDNS, AdGuard and others) and compares the answers. Useful when you have just changed a record and want to verify whether the new value has propagated past your local resolver's cache. Results are collected in parallel so the check completes in the time of the slowest resolver, not the sum.

DNSSEC Validation

Checks for the presence of DNSKEY, DS and RRSIG records to confirm that DNSSEC is active and the chain of trust is in place between the parent zone and the authoritative nameservers.

Network Tools

Ping, Traceroute and Port Scanner are executed server-side, giving you an external, third-party view of your infrastructure — useful for distinguishing "down for everyone" from "only for me". Traceroute is implemented via TTL-incremented ICMP echo requests (TTL 1–30). Port Scanner uses parallel TCP connect with a per-port timeout, covering the most common service ports.

Spam / RBL Checker

Tests a given IP address against 30+ widely-used Realtime Block Lists (DNSBL/RBL) that major mail providers consult when filtering inbound email. Checks are parallelised so results return quickly even with a large number of lists. A listing on one of these databases is frequently the reason legitimate email lands in spam.

WHOIS & Abuse Lookup

WHOIS queries are sent directly to the authoritative registry WHOIS server over TCP port 43, returning raw registration data: registrant, registrar, creation/expiry dates and nameservers. Abuse Lookup resolves the abuse contact for an IP block by querying the relevant Regional Internet Registry (ARIN, RIPE, APNIC, etc.).

Technical Stack

  • DNS resolution: DnsClient.NET library, 5-second timeout per query, querying system resolvers and public recursive resolvers by type.
  • IP geolocation: ip-api.com (non-commercial free tier).
  • ASN / BGP data: bgpview.io REST API.
  • MAC vendor lookup: macvendors.com OUI database.
  • Reverse lookup database: SQL Server, populated organically from all DNS queries made on this site. No third-party data.
  • Web framework: ASP.NET Core 10, deployed on Windows Server.

Limitations

All DNS queries are made from a single server location. Results represent what is visible from that vantage point. For multi-location propagation testing, use the Propagation Checker. The reverse lookup database is entirely self-populated — domains not yet queried on this site will show no history. Data grows organically with usage.

Rate limits apply to some third-party data sources (ip-api.com, bgpview.io). If a tool returns an error mentioning a rate limit, please wait a minute and try again.

Feedback & Improvements

This tool is continuously improved based on real-world usage. If you encounter an incorrect result, a missing check or a bug, please get in touch via the contact information in the footer. Contributions and suggestions from the technical community are what make tools like this better over time.