What information does it show about the certificate?

The issuing certificate authority and the expiry date, the two most commonly needed details for a quick certificate health check.

Why does SSL certificate expiry matter?

An expired certificate breaks HTTPS for visitors, typically showing a security warning in their browser — checking expiry ahead of time avoids that surprise.

Does this work on any domain, or just ones I own?

It works on any publicly accessible domain, useful for checking your own site or verifying a third-party site's certificate status.

Does SSL Certificate Checker upload my files to a server?

No. SSL Certificate Checker runs entirely in your browser using on-device processing, your files never leave your device.

SSL Certificate Checker

Check a domain's SSL certificate issuer and expiry date.

Processed on our server

Domain name

About this tool

Confirming a domain's SSL certificate is valid and checking exactly when it expires matters for avoiding a surprise expiration that breaks HTTPS for site visitors, and that information isn't always obvious just from browsing the site. This tool checks a domain's SSL certificate issuer and expiry date, giving you a direct answer instead of digging through browser certificate details.

Frequently asked questions

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