Codynet — Network tools that just answer the question.
Codynet<br>Network tools that just answer the question.<br>DNS, RDAP, HTTP, TLS, and subnet investigations — deterministic, free, with no query retention.<br>Open the toolboxHow it works<br>No accounts. No query retention. Privacy-respecting analytics.
$ query codynet.com MX<br>status: ok<br>records:<br>priority: 10<br>exchange: mail.example.net
$ rdap domain codynet.com<br>source: HTTPS RDAP<br>result: structured registration data
Featured tools<br>Small by design, reusable under the hood.
All tools<br>DNS Lookup<br>Resolve common DNS record types with structured output.<br>Open tool DIG Lookup<br>Packet-level DNS queries with raw output, sections, flags, and TTLs.<br>Open tool NSLookup<br>Quick A, AAAA, CNAME, and NS checks in a familiar flow.<br>Open tool MX Lookup<br>Inspect mail exchanger records and priorities.<br>Open tool TXT Lookup<br>Review SPF, DKIM, verification, and other text records.<br>Open tool Reverse DNS (PTR)<br>Resolve an IP back to its hostname via PTR records.<br>Open tool<br>Popular lookups: online nslookup tool, MX record lookup, online dig tool, TXT record lookup, reverse DNS (PTR) lookup, and DNS lookup.
Start with a workflow<br>Not sure which tool you need? Start from the job you're doing.
Debug DNS propagation<br>Run the same record across Cloudflare, Google, and Quad9 to see who has the new answer yet.<br>Compare resolvers Check a domain's email DNS<br>Confirm MX routing, then read SPF, DKIM, and DMARC in the TXT records that authenticate mail.<br>Check email DNS Check TLS certificate health<br>Inspect the certificate chain, expiry date, names, and trust before users hit an error.<br>Inspect a certificate Audit HTTP security headers<br>Follow redirects and review HSTS, CSP, and the other response headers that harden a site.<br>Check headers Launch or move a domain<br>Learn which DNS records to set, then verify each one with the matching lookup tool.<br>Read the guide Audit many names at once<br>Run any lookup over a list of domains or IPs and export the results as JSON or CSV.<br>Run bulk lookups
Guides<br>Plain-English explanations behind the tools.
All guides<br>DNS Records Explained<br>A practical guide to A, AAAA, CNAME, MX, TXT, NS, CAA, and other DNS record types.<br>Read guide MX Records And Email Routing<br>How mail exchanger (MX) records control email routing for a domain, and how to troubleshoot MX routing when mail delivery breaks.<br>Read guide SPF, DKIM, And DMARC Explained<br>A domain owner's guide to the DNS records that help receivers trust email.<br>Read guide SPF Record Failing? How To Read It In DNS<br>How to find your SPF record in DNS, read every mechanism and qualifier, and fix the real failures: softfail to spam, the 10-lookup permerror, and duplicate records.<br>Read guide TLS Certificate Expiration And Troubleshooting<br>How to inspect certificate dates, names, issuers, and trust problems before users see errors.<br>Read guide NXDOMAIN vs SERVFAIL: What DNS Errors Actually Mean<br>What is NXDOMAIN and what is SERVFAIL? NXDOMAIN means the DNS name does not exist; SERVFAIL means the resolver could not get a clean answer. Two different DNS errors, two different fixes.<br>Read guide
Why Codynet is different<br>Built to answer one question fast, then get out of your way.
Deterministic answers<br>Lookups run against real DNS resolvers and HTTPS RDAP endpoints, and show you the raw, structured response — not a guess or a cached marketing page.
No query retention<br>Codynet runs your lookup and does not log or retain the values you search. Your history stays in your browser, and analytics are privacy-respecting.
Tools that connect<br>Results link straight into the next tool — an IP to its reverse DNS and owner, a host to its DNS and TLS — so an investigation flows without retyping.
Free and account-free<br>No sign-up, no paywall, no project setup. Open a tool, run the lookup, and copy or export what you need.
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