SSL Checker — Check SSL Certificate & Expiry Online
Enter any domain to instantly check its SSL certificate status, issuer, issue and expiry dates, days remaining, and all subject alternative names (SANs). Fully client-side — your domain is never stored.
Press Enter, or use the Check SSL button in the header.
Subject Alternative Names (SAN)
Certificate data is fetched live from public Certificate Transparency logs (crt.sh). Reachability is checked with a plain HTTPS request to the domain.
Frequently Asked Questions
An SSL/TLS certificate is a digital certificate that encrypts the connection between a visitor's browser and a website's server. It verifies that the site is genuinely operated by the organisation it claims to represent and enables the secure HTTPS padlock in the address bar.
Most modern SSL certificates are valid for 90 days to 1 year. Our checker tells you exactly how many days are left before the current certificate expires, so you can renew it in time and avoid security warnings for your visitors.
A SAN is an additional domain name listed on the same certificate. A single certificate can cover multiple domains — for example www.example.com, api.example.com and mail.example.com. The SAN list shows every domain your certificate currently protects.
Green means 30 or more days remain, yellow means 7–29 days remain, and red means the certificate expires in under 7 days or has already expired. We recommend renewing well before the red zone.
No. Everything runs in your browser and results are fetched live from public certificate logs. We do not store, log or share any domain you check.
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