About SSL Checker
This free SSL checker tests the HTTPS certificate of any website. Type a domain name or paste a URL and our server connects to it on port 443, the way a browser does. You get a clear verdict, the expiry date and days left, whether the certificate covers the address you typed, whether browsers trust its chain, the TLS version and the cipher, and every certificate in the chain with its full details.
It flags the problems that cause browser warnings: expired or not-yet-valid certificates, a certificate issued for another name, self-signed certificates, missing intermediate certificates, outdated TLS versions and weak keys or signatures. The address you check is not stored.
How to use SSL Checker
- 01
Type a domain name or paste a URL.
- 02
Click Check SSL.
- 03
Read the verdict, the expiry date, the TLS version and the certificate chain.
When to use it
- Checking a certificate right after installing or renewing it.
- Finding out when a website’s certificate expires.
- Fixing “your connection is not private” warnings.
- Spotting a missing intermediate certificate (CA bundle).
- Checking a client’s or supplier’s website before a launch.
Frequently asked questions
How does the check work?
Our server connects to the site on port 443 (HTTPS), like a browser, and reads the certificate chain and the connection details. The address you check is not stored.
What does “not trusted” mean?
Browsers could not link the certificate to an authority they trust. Usually an intermediate certificate is missing on the server: install the full chain (CA bundle) with your certificate.
Can it check internal servers?
No. For safety only public websites on port 443 can be checked. For an internal certificate, paste it into the certificate decoder instead.