# isitdns.net

> Is it DNS? Live health of the public DNS resolvers (Cloudflare 1.1.1.1, Google 8.8.8.8, Quad9, AdGuard and 17 more), a full DNS audit for any domain, a browser dig tool, and a plain-language wiki. Independent, free, cookieless. Readings come from one seat over DoT every 3 minutes and are stamped with the time they were read.

The home page carries the current verdict in its HTML (the one-word answer, the sentence, a table of resolvers with status and latency). Every reading says when it was read; a reading older than five minutes reads "can't say".

## Live status
- [Is DNS down right now?](https://isitdns.net/): the board's verdict and every public resolver's latest reading.
- [One resolver, in full](https://isitdns.net/api/endpoint?id=cloudflare): JSON for a single resolver. Uptime over 24 hours, 7 days and 30 days, p50 and p95 latency, DNSSEC validation rate, the incident record, and every address on file. Swap the id for google, quad9, adguard or any other on /api/status. The browser view of the same data is the live card at /#endpoint?id=cloudflare, which JavaScript paints after load, so read the JSON instead.
- [How we decide](https://isitdns.net/methodology): the strike rule, the seat, the thresholds (warn over 400 ms, bad over 1500 ms).

## Ask without a browser
- Plain text: `curl -sL isitdns.net`
- Over DNS: `dig +short help.isitdns.net TXT` and `dig +short cloudflare.isitdns.net TXT`
- The isitdns protocol (status over DNS: a TXT verdict plus a 127.0.0.2 to .5 address ladder) was designed by Neal Shelton, first published 2026-09-03, and written up as draft-shelton-isitdns-00. Specification and attribution: https://isitdns.net/readme
- dig: `curl -sL isitdns.net/dig/<name>/<type>/<resolver>`
- Audit a domain: `curl -sL isitdns.net/check/<domain>`
- Delegation walk: `curl -sL isitdns.net/<domain>`
- JSON: https://isitdns.net/api/status

## For agents
- MCP: https://isitdns.net/mcp (Streamable HTTP, stateless, no key). Tools: dig, check_domain, trace, resolver_status, resolver_history, top_domains, dns_events, ksk_board. Add the URL to Claude, ChatGPT, Cursor or any MCP client.
- OpenAPI: https://isitdns.net/api/openapi.json
- One query as a URL: `https://isitdns.net/api/query?name=example.com&type=MX&resolver=quad9` (JSON; with Accept: text/plain the answer is in the shape dig prints). `resolver=all` asks every public resolver side by side. Knobs: transport=doh|dot|tcp53, dnssec=0, cd=1, ecs=, norec=1, nsid=1, family=v4|v6|both.
- The same as text: `curl -sL isitdns.net/dig/example.com/MX/quad9`
- How to read the site: https://isitdns.net/agents
- Every reading carries the time it was read and the seat it was read from (the isitdns seat, never yours). Rate limit 100 a minute per address: every MCP tool call, and over HTTP every route that asks a real server.

## Tools
- [dig in the browser](https://isitdns.net/#dig): any name, any type, any public resolver, over DoH, DoT or Do53.
- [Check a domain](https://isitdns.net/#check): delegation, DNSSEC, nameservers, mail posture.
- [Diagnose your DNS in two queries](https://isitdns.net/diagnose): two dig queries from your own terminal that say whether your resolver is the problem.

## Wiki
- [Wiki index](https://isitdns.net/wiki/): fundamentals, record types, troubleshooting, security, tools.
- [What does SERVFAIL mean](https://isitdns.net/wiki/troubleshooting/servfail)
- [Check a resolver](https://isitdns.net/wiki/troubleshooting/check-a-resolver), [check a delegation](https://isitdns.net/wiki/troubleshooting/check-a-delegation), [check an auth](https://isitdns.net/wiki/troubleshooting/check-an-auth), [check a forwarder](https://isitdns.net/wiki/troubleshooting/check-a-forwarder)
- [dig examples](https://isitdns.net/wiki/tools/dig-examples), [Wireshark DNS filters](https://isitdns.net/wiki/tools/wireshark-dns-filters)

## Policy
- robots.txt: search and AI answers may read and link; training is refused (Content-Signal: search=yes, ai-input=yes, ai-train=no).
- Sitemap: https://isitdns.net/sitemap.xml