How to use the website uptime checker
- 1Enter your site's address and press Check uptime.
- 2Read the verdict, then the Status, Response time, Time to first byte and Page title.
- 3Press Check again to repeat; earlier results stay under Checks in this session until you leave the page.
Example: how results are worded
Four different outcomes of a check
200 → Up: it's responding for us 503 → Down: the server returns an error DNS lookup failed → Down: the domain doesn't resolve No answer in 10 s → Down: no response
These are the tool's verdicts. A failure of our own checker is reported separately as “We couldn't tell”, never as your site being down.
One-off checks vs continuous monitoring
This tool answers one question: does the site respond right now? Our server requests the page once, follows redirects and reports what happened. Monitoring repeats that check every minute or few minutes, from several locations, records the history and alerts you by email or SMS when it fails twice in a row. Use this checker to confirm a suspected outage or test a fix; use a monitoring service to know about outages before your customers do.
Reading status and response time
- Status 2xx: up. 3xx redirects are followed and the final page is reported.
- 4xx: the server is up but this URL fails (404) or refuses automated requests (403, 429).
- 5xx: the server or application is failing: down for visitors.
- Response time is the total for every request including redirects; time to first byte is how long the server took to start answering the final request. web.dev considers a TTFB up to 0.8 s good. Times are measured from our server, so your own will differ by network distance.
What uptime percentages mean in minutes
| Uptime | Downtime per month (30.4 days) | Downtime per year |
|---|---|---|
| 99% | 7 h 18 min | 3 days 15 h |
| 99.5% | 3 h 39 min | 1 day 20 h |
| 99.9% | 43 min 50 s | 8 h 46 min |
| 99.95% | 21 min 55 s | 4 h 23 min |
| 99.99% | 4 min 23 s | 52 min 36 s |
Hosting SLAs usually exclude planned maintenance, and they compensate with credits rather than preventing downtime.
Checking from more than one location
Every check here comes from our server, in one location. A site can be up for us and down in another region, for example when a CDN edge, a DNS provider or a regional network fails, or when a firewall blocks certain countries. Monitoring services that check from several continents catch those partial outages. If visitors report problems you can't reproduce, ask them for the error message and the result of is it down from their side.
Setting up free monitoring
Several monitoring services have free plans that check a handful of URLs every five minutes and alert by email. When choosing one, check the interval, how many locations confirm an outage before alerting (fewer false alarms), whether it checks for a keyword on the page (catches "200 OK" error pages), and whether it watches HTTPS certificate expiry. Monitor the homepage plus one page that hits the database, such as search or a product page.
What happens to the address I enter?
To check a URL, our server requests the address you enter and returns the result to you. We don't store the pages we fetch or keep a list of the addresses you check. Like any website, our hosting provider keeps short-lived technical request logs for security. See the privacy policy.