About WhereIsDNS

What this is

WhereIsDNS is a free tool that lets you check how a domain's DNS records look from 12 different public DNS resolvers around the world — Cloudflare, Google, Quad9, OpenDNS, AdGuard, NextDNS, Yandex, AliDNS, DNSPod, CleanBrowsing, Mullvad, and ControlD. It's the fastest way to confirm a DNS change has gone global, or to diagnose why one user can reach a site and another can't.

How it works

When you submit a lookup, a small Cloudflare Worker fans out 12 DNS-over-HTTPS queries in parallel — one to each resolver. Results stream back to your browser the moment each resolver responds, so the slowest one doesn't hold up the rest. Total round-trip is usually 200–500 ms.

The location labels reflect each resolver operator's nominal jurisdiction, not a physical multi-vantage probe. The actual query originates from the Cloudflare edge nearest your browser. For most propagation troubleshooting that's enough.

Open source

The full source is on GitHub at github.com/cmunkres/whereisdns. It's a Vite + React frontend + a single Cloudflare Worker, no backend database, no accounts.

Why ads?

Running a global service for free isn't actually free — domains, hosting, and time all cost something. WhereIsDNS shows two unobtrusive Google AdSense slots so the tool can stay free for everyone, no signup, no rate limits for normal use. If you run an ad blocker, the site still works perfectly.

Contact

Found a bug? Got a feature request? Want to suggest a resolver to add or swap out? Open an issue at github.com/cmunkres/whereisdns/issues. For privacy questions specifically, see our Privacy Policy.