Site Downtime Checker
Enter a URL below and we run it through 12 outside-in checks — the same kind of checks a monitoring tool would run every few minutes — so you know whether a site is actually down, not just slow on your connection.
100 of 100 free scans left today. We verify your email first — it keeps bots and AI scrapers from draining the daily pool, and it's where your report lands. Limits: one scan per email per day, one per connection per day.
We emailed a 6-digit code to . Enter it to start the scan — it expires in 10 minutes.
What the 12 checks cover
The scan hits the homepage from outside your own network and times the response, so a slow-but-technically-up site shows up differently from one that isn't responding at all. It also checks the TLS certificate (valid and not about to expire), DNS resolution, whether plain-http requests redirect to https, and domain registration expiry — the kind of failure that looks fine one day and is a dead domain the next.
A few checks aren't about uptime at all but still matter if a domain starts failing: SPF, DMARC, and MX records affect whether your mail gets delivered or spoofed. A site can be fully "up" while its email quietly breaks.
What "down" can actually mean
"Down" covers more than a blank browser tab. It can mean the server isn't responding, DNS is pointing nowhere, a TLS certificate expired and browsers are blocking the page, or the site loads but a broken deploy is returning errors on every request. Each of those needs a different fix, which is why a single check gives you more than a yes/no answer.
We verify your email before running the scan — it keeps bots and scrapers from draining the free daily pool, and it's where your full report lands. Expect a 6-digit code by email first, then live results in under a minute — not a zero-click scan.
Holter watches this for you: outside-in monitors plus dead-man heartbeats for silent failures. Free plan: 5 monitors, 5-minute checks, no credit card.
Start monitoring — free