Is It DNS or the Connection?
When something will not load, find out which of the two layers is broken.
Run the test
Each sample is a real HTTP request to the nearest Cloudflare edge, with the response read in full. It is not an ICMP ping: it includes the server’s own handling time and stops at the edge rather than reaching any particular destination.
Where this comes from
Two checks that fail independently. A name is resolved over DNS-over-HTTPS — which reaches a resolver over the same HTTPS path ordinary traffic uses, deliberately bypassing whatever resolver the device is configured with — and a request is made for content. Four outcomes follow, and three of them are diagnoses. Both working means neither layer is broken from here. Traffic flowing while resolution fails is almost always the resolver rather than the line. Resolution working while traffic does not is usually a captive portal or a firewall. Both failing is a connection that is simply down.
What the results mean
- Name resolution working
- A DNS query over HTTPS succeeded. Because it bypasses your configured resolver, this can pass while your device still cannot resolve anything.
- Connectivity working
- A request for content completed. The transport is fine whatever DNS is doing.
- Traffic without resolution
- The classic ISP-resolver failure, or a filtering resolver blocking a name. Changing the resolver on the device confirms it in a minute.
- Resolution without traffic
- Usually a captive portal waiting for a sign-in, or a firewall. Opening any plain http address will reveal a portal immediately.
Common problems and fixes
- Everything here works and one site still will not load
- The problem is that site, its route, or something filtering it specifically. Both layers being fine is genuinely useful information — it rules out the two things people change first.
- Resolution fails here but my browsing works
- Your device is resolving through a resolver that works while DNS-over-HTTPS is being blocked — some networks and some routers block it deliberately.
- Both fail but the page loaded
- The page was loaded before the connection dropped. Reload it once the connection is back to get a current answer.
Frequently asked questions
Is it my DNS or my internet connection?
The distinguishing test is to resolve a name over a path that does not use your configured resolver, which is what DNS-over-HTTPS gives you. If that succeeds while ordinary browsing fails to find anything, the transport is fine and the resolver is the problem — changing it on the device fixes it. If resolution works and content will not load, the transport is the problem and DNS is a red herring.
What is a captive portal?
The sign-in page a hotel, airport or café network puts in front of you. Until you sign in, DNS often works while everything else is intercepted — which produces exactly the "names resolve, nothing loads" result above. Opening any plain http address will bounce you to the portal.
Should I change my DNS server?
It is worth trying when resolution specifically is failing, and it is a two-minute change that is easy to undo. It is not a general performance fix — DNS is a few milliseconds of a page load, and changing it does nothing for a connection problem.
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