Free tool

SSL
CHECKER

Enter a domain to inspect the SSL/TLS certificate it serves: who issued it, when it expires, how many days remain, which hostnames it covers, and whether the certificate chain is valid and trusted by browsers.

What is an SSL Checker?

An SSL checker is a free tool that inspects the SSL/TLS certificate a website serves. It reports who issued the certificate, when it expires, how many days remain, which hostnames it covers, and whether the certificate chain is valid and trusted by browsers, so you can confirm a site’s encryption is set up correctly.

How does an SSL Checker work?

  1. 01We open a TLS connection to the domain on port 443.
  2. 02The served certificate is read: issuer, validity window and covered names.
  3. 03We flag anything expiring soon, expired, self-signed or untrusted.

Frequently asked questions

What does the SSL checker tell me?

It reports the certificate issuer, the valid-from and valid-to dates, the days remaining before expiry, every hostname the certificate covers (its Subject Alternative Names), and whether the chain is valid and trusted by browsers. An expired, self-signed or mismatched certificate is flagged clearly.

My certificate expires soon. What should I do?

Most reputable hosts issue and auto-renew free SSL certificates through Let’s Encrypt, so a certificate expiring in under 30 days usually means auto-renewal is not configured. If yours is not renewing itself, that is a sign to move to a host that manages SSL for you.

Is a valid certificate enough to be secure?

A valid certificate encrypts traffic, but real security also depends on the host: a web application firewall, malware scanning, DDoS protection and fast patching. Our security-focused hosting guides rank hosts on exactly those signals.

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