How to check if a website is down
Enter the URL above and run a check — the monitor sends a real HTTP request and reports whether your site returned a successful response. A 200 OK means the server is up; a timeout or 5xx error means the server could not respond.
How uptime monitoring works
Uptime monitoring sends automated HTTP requests to your website or API endpoint on a regular schedule and records whether each request succeeded, failed, or timed out. When a failure is detected, you are alerted before your users notice the problem. Scheduled monitors run every 1–60 minutes depending on your plan and probe from multiple geographic regions.
What is measured
- Availability — whether your server returned a successful HTTP response (2xx or 3xx status code).
- Response time (latency) — how long the server took to respond, measured in milliseconds.
- SSL certificate validity — whether the certificate is valid, trusted, and not expiring soon.
Uptime percentage explained
Uptime percentage is calculated as the ratio of successful checks to total checks over a given period. Common SLA targets: 99.9% allows ~43 minutes of downtime per month; 99.99% allows ~4.3 minutes; 99.999% (five nines) allows ~26 seconds. Most hosted services and cloud providers publish SLAs in this format.
Free uptime monitoring — Uptime Robot, Pingdom, and alternatives
Uptime Robot offers free monitoring with 5-minute check intervals and is one of the most widely used free uptime services. Pingdom is a paid service with more detailed performance reporting. This tool provides free one-time checks from multiple regions without an account, plus free scheduled monitoring on sign-up — useful when you want to check website status quickly without setting up a third-party service.
What causes false positives?
A single failed check may be a transient network issue rather than genuine downtime. This monitor requires consecutive failures before treating an event as real downtime, reducing noise from brief connectivity glitches. Multi-region probing further reduces false positives: if probes from Frankfurt, São Paulo, and Singapore all fail simultaneously, that is genuine downtime — not a routing fluke.
Frequently asked questions
Is this website down right now?
Enter the URL above and run a check — the result shows the HTTP status code and response time from each probe region. If the check returns a timeout or 5xx error from all regions, the site is down. If it succeeds from some regions but not others, the issue may be geographic or CDN-related.
What is a good uptime percentage?
For most web applications, 99.9% uptime (about 9 hours of downtime per year, or 43 minutes per month) is an acceptable baseline. Mission-critical services target 99.99% (~52 minutes per year) or higher. "Five nines" (99.999%) requires automated failover and redundant infrastructure — about 26 seconds of downtime per year.
How is website uptime monitoring different from a website status checker?
A website status checker runs a one-time check to see if a site is currently up. Uptime monitoring runs checks on a schedule — every 1, 5, or 15 minutes — and stores the history so you can see patterns, response time trends, and past incidents. This tool does both: one-time checks without an account, and scheduled monitoring with an account.
What HTTP status codes indicate a site is down?
5xx codes (500 Internal Server Error, 502 Bad Gateway, 503 Service Unavailable, 504 Gateway Timeout) indicate server-side failures. A connection timeout means the server did not respond at all. 4xx codes (400, 403, 404) indicate the server responded but returned a client error — the server itself is up, but the specific URL or request failed.