SSL Checker

What is SSL/TLS?

SSL (Secure Sockets Layer) and TLS (Transport Layer Security) are cryptographic protocols that provide secure communication over the internet. SSL certificates enable HTTPS connections, encrypting data between clients and servers. SSL certificates contain information about the certificate authority, expiration date, domain name, and public key.

Our free SSL Checker helps you verify if a domain supports HTTPS and provides basic SSL information. For detailed certificate information (issuer, expiration, validity), use browser developer tools or specialized SSL checking services.

Why Check SSL Certificates?

Checking SSL certificates is important for:

• Verifying HTTPS support and security
• Checking certificate expiration dates
• Validating certificate authority and chain
• Ensuring proper SSL/TLS configuration
• Security audits and compliance

SSL Certificate Information

• Issuer: Certificate Authority (CA) that issued the certificate
• Subject: Domain name the certificate is issued for
• Valid From/To: Certificate validity period
• Public Key: Public key for encryption
• Signature Algorithm: Algorithm used to sign the certificate

Common SSL Issues

• Expired Certificate: Certificate has passed expiration date
• Invalid Domain: Certificate doesn't match domain name
• Untrusted CA: Certificate from untrusted certificate authority
• Mixed Content: HTTPS page loading HTTP resources
• Weak Cipher: Outdated or weak encryption algorithms

Best Practices

• Use Valid Certificates: Ensure certificates are not expired
• Monitor Expiration: Set up alerts for certificate expiration
• Use Trusted CAs: Obtain certificates from trusted certificate authorities
• Enable HSTS: Use HTTP Strict Transport Security header
• Regular Checks: Periodically check SSL configuration

FAQs

How do I check full SSL certificate details?

Use browser developer tools (Security tab), SSL Labs SSL Test, or command-line tools like openssl.

What is certificate expiration?

SSL certificates have expiration dates. Renew certificates before expiration to maintain HTTPS support.

What is a certificate authority?

A Certificate Authority (CA) is an organization that issues SSL certificates. Browsers trust certificates from recognized CAs.

How do I fix SSL certificate errors?

Common fixes include renewing expired certificates, ensuring domain matches, and using certificates from trusted CAs.

What is the difference between SSL and TLS?

TLS is the successor to SSL. Both provide encryption, but TLS is more secure. The term "SSL" is often used to refer to both.