A site that won't load in your browser isn't necessarily down — it might just be down for you. Telling the two apart requires checking from somewhere else entirely, which is exactly what this tool does: it fetches the URL live from this site's own server, not yours.
Why a Site Can Look Down When It Isn't
Several local causes can make a perfectly healthy site unreachable from one specific device or network: a stale DNS cache still pointing at an old IP after the site moved hosts, a route blocked somewhere between you and the server, a misconfigured local DNS resolver, or even a browser extension interfering with the request. None of these have anything to do with the site itself — checking from a neutral external server rules all of them out in a single step.
How the Check Actually Works
The tool fetches the URL directly, following redirects, and reports the final HTTP status code and how long the response took. Reachability is judged the same way a browser effectively would:
- Up — the server responded, including with a normal error page (a 404, for instance). A response means the server is listening and answering requests.
- Down — either no response at all (connection refused, timed out), or a 5xx server error. From a visitor's perspective, a server that's crashing on every request is indistinguishable from one that isn't there at all.
- Down (too many redirects) — a redirect chain that never actually lands on a page. A real chain that long hasn't resolved, whatever the underlying cause.
Status Code, Not Just Up/Down
The status code itself narrows down what's actually wrong once a site is confirmed down: a 5xx means the server itself is erroring, while a connection that never completes at all points further down the stack — DNS, routing, or the server process not running. For the deeper version of that breakdown, a Website Health Check runs DNS, ping, HTTP, and SSL together instead of just the one HTTP fetch this tool performs.
Frequently Asked Questions
The site loads for me now but this tool said it was down a minute ago — why?
A transient blip — a brief server restart, a momentary spike in load, or a load balancer routing a single request to an unhealthy instance — can cause one check to fail without meaning the site is genuinely unreliable. Run it again; a site that's consistently down across several checks is a different situation than one flaky result.
Why does a site that returns a 404 count as "up"?
Because the server responded — it's working, just telling you the specific page doesn't exist. That's a completely different problem from the server being unreachable, and conflating the two would make this check useless for telling them apart.
Is this the same as a ping?
No — Ping tests raw network reachability over ICMP, which firewalls commonly block even on a perfectly healthy site. This tool fetches the URL over real HTTP, the same protocol a browser uses, so it answers "can a visitor actually load this page" more directly than ping does.
Check whether a site is actually down with Is My Site Down.