SSL Certificate Checker
Verify SSL/TLS certificates, check expiration dates, and ensure your website's security
Check SSL Certificate
Enter domain without https:// (e.g., example.com)
Common SSL Issues
Frequent SSL certificate problems and how to fix them
Expired Certificate
SSL certificate has passed its expiration date
Renew your SSL certificate before it expires. Set up auto-renewal if using Let's Encrypt.
Self-Signed Certificate
Certificate not issued by a trusted authority
Obtain a certificate from a trusted Certificate Authority (CA) like Let's Encrypt, DigiCert, or Sectigo.
Name Mismatch
Certificate domain doesn't match the website domain
Ensure the certificate is issued for the correct domain. Use wildcard certificates for subdomains.
Weak Encryption
Using outdated SSL/TLS protocols or weak ciphers
Upgrade to TLS 1.2 or TLS 1.3. Disable SSLv2, SSLv3, TLS 1.0, and TLS 1.1.
What is an SSL Certificate?
An SSL (Secure Sockets Layer) certificate is a digital certificate that authenticates a website's identity and enables an encrypted connection. SSL certificates are now technically called TLS (Transport Layer Security) certificates, but the term SSL is still commonly used.
SSL certificates are essential for website security. They protect sensitive data like login credentials, credit card information, and personal details from being intercepted by attackers. Websites with SSL certificates display a padlock icon in the browser and use HTTPS instead of HTTP.
Modern browsers mark websites without SSL certificates as 'Not Secure,' which can damage trust and hurt SEO rankings. Google considers HTTPS a ranking factor, making SSL certificates crucial for both security and search engine optimization.
How to Check SSL Certificates
Step 1: Enter Domain Name
Type the domain name you want to check. No need to include https:// or www - just the domain name.
Step 2: Run Certificate Check
Click the check button to analyze the SSL certificate. The tool will verify validity, expiration, issuer, and security protocols.
Step 3: Review Certificate Details
Examine the certificate information including issuer, validity period, encryption protocol, and cipher suite.
Step 4: Take Action if Needed
If issues are found, renew expired certificates, fix name mismatches, or upgrade to stronger encryption protocols.
SSL/TLS Protocol Comparison
Understanding the evolution of SSL/TLS security protocols
| Protocol | Released | Status | Security Level |
|---|---|---|---|
| SSL 2.0 | 1995 | Deprecated | Insecure - Multiple vulnerabilities |
| SSL 3.0 | 1996 | Deprecated | Insecure - POODLE attack |
| TLS 1.0 | 1999 | Deprecated | Weak - Should not be used |
| TLS 1.1 | 2006 | Deprecated | Weak - Should not be used |
| TLS 1.2 | 2008 | Current | Secure - Widely supported |
| TLS 1.3 | 2018 | Current | Most Secure - Recommended |
SSL Certificate Best Practices
How to maintain secure and valid SSL certificates
Use Trusted Certificate Authorities
Obtain certificates from reputable CAs like Let's Encrypt, DigiCert, or Sectigo. Avoid self-signed certificates for production websites.
Enable Auto-Renewal
Set up automatic certificate renewal to prevent expiration. Let's Encrypt certificates expire every 90 days and should be renewed automatically.
Use Strong Encryption
Enable TLS 1.2 and TLS 1.3 only. Disable older protocols (SSLv2, SSLv3, TLS 1.0, TLS 1.1) and weak cipher suites.
Implement HSTS
Use HTTP Strict Transport Security (HSTS) to force browsers to always use HTTPS connections and prevent downgrade attacks.
Monitor Certificate Expiration
Set up monitoring and alerts for certificate expiration. Check certificates regularly and renew at least 30 days before expiration.
Use Wildcard or Multi-Domain Certificates
For multiple subdomains, use wildcard certificates (*.example.com) or SAN certificates to cover multiple domains with one certificate.