Certificate Details
Validity Period
Subject Alternative Names (SANs)
Certificate Chain
Security Checks
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Frequently Asked Questions
An SSL (Secure Sockets Layer) certificate is a digital certificate that authenticates a website's identity and enables an encrypted connection. When a site has SSL, you see HTTPS in the URL and a padlock icon in the browser, indicating secure communication.
A+ is the highest grade indicating excellent security with modern protocols and strong encryption. A is very good, B is acceptable but could be improved, C has some issues, D has significant problems, and F indicates the certificate is invalid, expired, or has critical security issues.
SSL certificates have a limited validity period, typically 90 days to 1 year. If your certificate is expiring soon, you need to renew it before the expiration date to avoid security warnings for your visitors. Services like Let's Encrypt offer free auto-renewal.
A certificate chain (or chain of trust) links your SSL certificate to a trusted root certificate authority (CA). It typically includes your domain certificate, intermediate certificate(s), and the root CA certificate. Proper chain configuration is essential for browsers to trust your certificate.
SANs are additional domain names or subdomains that a single SSL certificate covers. For example, a certificate for example.com might also include www.example.com, api.example.com, and mail.example.com as SANs, allowing one certificate to secure multiple domains.