DNS Propagation

Enter a domain and a record type and this asks four public DNS resolvers — Cloudflare, Google, DNS.SB and AliDNS — what they are serving at this moment, then tells you whether they agree. Where one differs it is highlighted, and every answer carries the remaining TTL of the cached copy, so you can see exactly how long the old record has left. A 30-second auto-recheck is there because the honest answer to "is it done yet" is usually "not quite, wait", and refreshing by hand gets old.

It helps to know what propagation actually is, because the word is misleading and the misunderstanding causes real panic. Nothing spreads anywhere. Your change is live at your nameservers the instant you save it. What takes time is every resolver that already cached the old answer letting go of it, and that happens when the TTL on that cached copy expires — the TTL that was in force before you made the change, not the one you set afterwards. This is also why nothing can speed it up: there is no button anywhere that flushes the world's caches, and any service claiming to "force propagation" is selling you a wait you were going to have anyway.

What this page checks, stated precisely: four resolver caches, queried straight from your browser, so nyaa.tools never sees the domain you type and has nothing to log. Four caches is not four countries — three of the four are global anycast networks that answer from whichever point of presence sits nearest to you, which is why they usually agree with each other. AliDNS, run by Alibaba in China, is the one most likely to still be holding a record the others have already let go.

Two things it deliberately does not claim. It cannot query your authoritative nameservers directly, because a browser has no way to talk to an arbitrary DNS server — to confirm a change at the source you still want dig @ns1.example.com. And it is not a twenty-location global map: a page running in your browser has exactly one vantage point, its own, and any tool that shows you a world map of results is either using its own servers or guessing.