When a website stops loading, the instinct is to blame the host and fire off an angry email. Sometimes that's right. Often it isn't — and if you can work out which layer is actually failing before you call anyone, you'll fix it faster, or at least raise the right ticket with the right people instead of losing an afternoon bouncing between them.
A website loading is a chain of separate steps, each depending on the one before. When it breaks, it breaks at a specific link in that chain. Here's how to walk the chain in order, from the cheapest check to the deepest.
First: is it actually down, or just down for you?
Before anything else, rule out the most common and most embarrassing cause: the problem being at your end. A surprising share of "the site is down" reports are local.
- Try the site on mobile data, with Wi-Fi off. If it loads on cellular but not on your network, the problem is your connection, your router, or your local DNS — not the website.
- Try a different device on a different network entirely.
- Use an external "is it down" check — a service that loads your site from elsewhere in the world. If it reports the site up, the outage is local to you.
- Try a hard refresh or a private/incognito window, to rule out a stale cached version.
If the site genuinely is down for everyone, now you diagnose where in the chain.
The chain, layer by layer
1. DNS — does the name still resolve?
Before a browser can reach your site, it has to turn your domain name into an IP address. If that lookup fails, nothing else can happen. Symptoms are usually a "server not found" or "can't resolve" error rather than a slow or broken page.
Common causes: the domain expired (the number-one cause people overlook — check the renewal status first), a DNS record was changed or deleted, or a nameserver change hasn't taken effect yet. Our guide to DNS TTL and propagation covers why a recent change might not be live everywhere yet, and our domain renewal checklist covers the expiry angle.
2. The connection — is the server reachable at all?
If the name resolves to an IP but nothing responds, the server itself may be down, overloaded, or unreachable. A timeout — the browser spinning and eventually giving up — points here. This is genuinely a host or server problem, and it's the case where contacting your hosting provider is the right move.
3. SSL/TLS — is it a certificate problem?
If the site loads but the browser throws a security warning — "your connection is not private," "certificate expired," "not secure" — the server is up and reachable, but its certificate is the problem. Almost always this is an expired certificate, and with certificate lifespans shrinking (as we've covered), this is an increasingly common cause for anyone not on automated renewal. The site isn't really "down" — it's the browser refusing to proceed, which to a visitor is the same thing.
4. The application — is it an error, not an outage?
If the server responds but returns an error — a "500 Internal Server Error," a database connection error, a white screen, a half-rendered page — then the infrastructure is fine and the problem is the site's own software. A recent update, a plugin conflict, a full disk, or a database that's stopped responding are typical. This is a developer or application problem, not a hosting one, even though it feels identical to the visitor.
The single most useful signal is the exact error. "Server not found" (DNS), a spinning timeout (connection/server), a certificate warning (SSL), and a "500" or database error (the application) point at four completely different layers and four different people to call. Read the error before you react to it — it's telling you where in the chain the break is.
A fast triage order
Put together, the quickest path from "it's down" to "I know whose problem this is":
- Check it's not just you — mobile data, another device, an external checker.
- Read the exact error message — it usually names the layer.
- Confirm the domain hasn't expired — a two-minute check that saves hours, and a genuinely common cause.
- Note whether there's a security/certificate warning — if so, it's SSL, and the server itself is fine.
- Distinguish "no response at all" from "an error page" — the first points at DNS or the host, the second at the application.
- Then raise it with the right party — registrar for expiry, host for a dead server, developer for an application error — with the specific error in hand.
Why this is worth learning even if you'll still call for help: walking in with "I'm getting a 500 error, the domain's current, and it loads fine on an external checker from another server" gets you to a fix far faster than "it's broken." You've already ruled out three layers and pointed straight at the fourth.
Frequently asked questions
How do I tell if my website is down for everyone or just me?
Load it on mobile data with Wi-Fi off, try another device on another network, and use an external "is it down" checker that loads the site from elsewhere. If those work, the problem is local to your connection or device.
My website shows a "server not found" error. What does that mean?
That's a DNS resolution failure — the domain name isn't turning into an IP address. Common causes are an expired domain, a changed or deleted DNS record, or a nameserver change that hasn't taken effect yet. Check the domain's renewal status first.
Is a certificate warning the same as my site being down?
Not technically — the server is up and responding — but to visitors it's just as blocking, because the browser refuses to load the page. It's almost always an expired SSL certificate, which is a separate fix from a genuine outage.
Should I call my hosting provider when my site goes down?
Only for the layers they control — an unreachable server or a genuine hosting fault. A DNS/expiry issue is a registrar matter, a certificate issue may be self-service, and a "500" or database error is an application problem for whoever maintains the site. Identifying the layer first tells you who to actually call.
Want someone who can diagnose the whole chain when a site goes down? Get in touch — that's the job.
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