SSL Certificate Checker
Verify your website's security instantly. Check SSL validity, expiration dates, and chain trust to ensure a safe browsing experience for your users.
Why Check Your SSL Certificate?
An SSL/TLS certificate is the digital backbone of website security. It encrypts data transmitted between your user's browser and your server, ensuring privacy and data integrity. But certificates have a finite lifespan. Just one day after expiration, modern browsers will block access to your site with a scary "Not Secure" warning.
Regularly checking your certificate status helps you:
- Avoid downtime caused by expired certificates.
- Verify that auto-renewal scripts (like Certbot) are functioning.
- Ensure the correct Certificate Authority (CA) is trusted.
- Maintain your SEO rankings (Google prefers HTTPS).
How to Read the Results
Valid From / Valid To
The specific date range during which the certificate is trusted. If the current date is outside this range, the cert is invalid.
Issuer (CN/O)
The Certificate Authority (e.g., Let's Encrypt, DigiCert) that verified your ownership of the domain.
Common Name (CN)
The primary domain the certificate was issued for. Mismatches here cause "Invalid Domain" errors.