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Free SSL tool

SSL Certificate Checker

Enter any domain name and instantly see its SSL certificate status, expiry date, issuer, and chain of trust. Catch problems before your visitors do.

What this tool checks

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Expiry date

See exactly how many days remain before the certificate expires — critical for avoiding unexpected browser warnings.

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Issuer & CA

Identify which Certificate Authority issued the certificate and verify it is from a trusted, recognized CA.

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Chain of trust

Verify that the full certificate chain (root → intermediate → leaf) is correctly configured and trusted by browsers.

How to check an SSL certificate

  1. Enter a domain — Type or paste any domain name — e.g. example.com — into the field above. No need to add https://.
  2. Click "Check SSL certificate" — The tool connects to the domain and retrieves the live certificate details.
  3. Review the results — You'll see the expiry date, issuer, validation level (DV / OV / EV), and whether the certificate chain is correctly configured.
  4. Take action if needed — If the certificate is expiring soon or the chain shows an error, browse certificate options or run our CA Chain Checker for deeper diagnosis.

Frequently asked questions

Why does my SSL certificate show as untrusted?

The most common causes are an incomplete chain (missing intermediate certificate), an expired certificate, or a mismatch between the domain on the certificate and the domain you are checking. Our tool flags each of these separately.

How often should I check my SSL certificate?

At minimum, check 30 and 7 days before expiry. Better practice is to set an automated reminder — use our free SSL Expiry Reminder tool to get email alerts automatically.

Does this tool work for subdomains?

Yes. Enter the full subdomain (e.g. mail.example.com) and the tool checks that specific certificate. For wildcard coverage, the result will show *.example.com as the subject.

Can I check an IP address instead of a domain?

SSL certificates are generally issued to domain names, not IP addresses (with narrow exceptions). Entering a raw IP usually won't return a valid match — use the domain name instead.

Need a new or replacement SSL certificate?

Browse all certificate types or take the 60-second quiz to find the right one.

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