SSL Certificate Checker

Check the certificate a host actually serves. We perform a real TLS handshake and report the issuer, validity window, remaining days, and chain.

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What this tool does

Inspect the TLS certificate presented by a public host.

How to use it

Enter a hostname and review the returned subject, issuer and validity dates.

Worked example

For example.com, compare the returned valid-to date with today; the precise date changes when certificates renew.

Limitations and checks

A certificate check is not a full website security audit. The result depends on the server route, SNI and certificate presented at lookup time.

How your data is processed

The lookup sends the domain, IP or URL to a SimpleTaskTools API and the external service needed for the lookup. Results reflect that service’s network vantage point. Do not submit private URLs, credentials or tokens.

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