Free tools for uptime and server monitoring
Small tools that need no account: check an SSL certificate or a domain expiry date, or calculate allowed downtime for an SLA.
Uptime Calculator
Turn an SLA percentage such as 99.9% into the downtime it allows per day, week, month, quarter and year, or work out the uptime percentage from minutes of downtime.
Read moreSSL Certificate Checker
Paste a website to see whether its HTTPS certificate is valid and how many days are left before it expires, with a response check from Poland, New York and Singapore.
Read moreDomain Expiry Checker
Paste a website to see when its domain registration expires and how many days are left, together with the SSL certificate and a response check from three locations.
Read moreTry Zuzia for free
New accounts get 14 days of the full Starter plan, no card. Then the Free Forever plan covers 1 host, 10 websites, 1 port check and 1 scheduled task. Add a host in about 30 seconds.