Check it now.

6 free checks that run from the same code as a monitor, and an uptime calculator. No account, one run, nothing saved.

Every tool

SSL checkerCheck an SSL certificate's expiry, chain and hostnameRUNS A CHECK Domain expiry checkerWhen does this domain expire?RUNS A CHECK DNS lookupLook up a DNS record from outside your networkRUNS A CHECK Mail checkCheck MX, SPF, DKIM, DMARC and four blocklistsRUNS A CHECK HTTP checkerCheck a URL's status, redirects and latencyRUNS A CHECK Port checkerIs this port open from the internet?RUNS A CHECK Uptime calculatorHow much downtime is 99.9% uptime?ARITHMETIC

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