Check whether a website's SSL certificate is valid, when it expires and which TLS version the server uses.
🎁 Your first website check is free – every security tool works on it. Need unlimited checks? Go Pro
🔒 We only make a normal HTTPS connection – the same thing every browser does.
How to use the ssl checker
- Enter a domain name, like example.com.
- We connect over HTTPS and read the certificate.
- Review validity, expiry, issuer, covered names and protocol.
Why SSL certificates fail
The most common causes are an expired certificate (auto-renewal broke), a missing intermediate certificate, or a certificate that doesn't cover the exact domain name (for example www vs non-www).
TLS versions
TLS 1.2 and 1.3 are current. TLS 1.0 and 1.1 are retired, blocked by modern browsers and fail PCI compliance for card payments.
Frequently asked questions
How do I check when my SSL certificate expires?
Enter your domain above – the expiry date and days remaining are shown at the top.
Why does my site say Not Secure?
Either there is no valid certificate, it has expired, or the page loads some content over plain HTTP.
Are free Let's Encrypt certificates OK?
Yes. They are trusted by all browsers; they just renew every 90 days, so automatic renewal must work.