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SSL Certificate Checker

Check a site's SSL/TLS certificate: issuer, expiry date, covered names, chain and protocol.

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How to use the SSL Certificate Checker

  1. 1

    Enter a domain name.

  2. 2

    See whether the certificate is valid, trusted and covers the domain.

  3. 3

    Review the expiry date, names covered and certificate chain.

Frequently asked questions

How does the check work?

Our server sends a request to the site you enter and shows you what came back. Nothing is stored, and the site sees our server, not you. We connect to port 443 and read the certificate the server presents.

What does "not trusted" mean?

Browsers can't link the certificate to a trusted authority. It is usually self-signed or missing an intermediate certificate on the server.

When should I renew?

Most certificates renew automatically 30 days before expiry. Check the setup if fewer than 30 days remain.