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SSL Certificate Checker

Verify SSL certificates, check trust status, and inspect security details

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Server Certificate

Common Name
SANs
Valid From
Valid To
Serial Number
Algorithm
Issuer

Connection Details

Protocol
Cipher Suite
Key Exchange
Key Type
Key Size
IP Address

OCSP Stapling

Enabled Not Supported

HSTS (HTTP Strict Transport Security)

Enabled Not Enabled
Max Age:

Warnings

Certificate Chain

Subject

Issuer

Fingerprints

SHA-256
SHA-1

Error

About SSL Certificate Checker

Our free SSL Certificate Checker lets you instantly verify any domain's SSL/TLS certificate. Enter a hostname to view its certificate details including issuer, validity dates, key type, cipher suite, protocol version, and full certificate chain. The tool connects directly to the server and retrieves real-time certificate information without any installation or registration required.

How to Use

  1. 1Enter the domain name (e.g., google.com) in the input field.
  2. 2Optionally change the port (default is 443 for HTTPS).
  3. 3Click "Check SSL" and view the complete certificate details.

Use Cases

  • •Verify SSL certificate installation before going live
  • •Check certificate expiry dates to prevent downtime
  • •Debug SSL/TLS connection issues
  • •Audit certificate chain completeness and trust
  • •Verify OCSP stapling and HSTS configuration

Related Tools

Certificate Decoder Security Scanner Key Matcher CSR Generator Key Generator Chain Builder

Technical Details

Supported Protocols

  • TLS 1.3, TLS 1.2, TLS 1.1, TLS 1.0
  • SSL 3.0 (deprecated)

Certificate Formats

  • PEM (Base64 encoded)
  • DER (Binary encoded)

Information Retrieved

  • Certificate chain and issuer details
  • Key type, size, and signature algorithm
  • SANs, serial number, fingerprints

Security Checks

  • OCSP stapling status
  • HSTS header detection
  • Certificate trust validation

Tips & Best Practices

  • •Always verify the certificate chain is complete — missing intermediates cause browser warnings.
  • •Check certificate expiry at least 30 days before expiration to allow time for renewal.
  • •Ensure HSTS is enabled with a max-age of at least 6 months for production domains.
  • •Use ECDSA certificates for better performance — they're 2-3x faster than RSA.

Frequently Asked Questions

A "not trusted" warning means the certificate chain is incomplete, self-signed, or issued by an unrecognized Certificate Authority. Browsers will show a security warning to users.
Check at least once a month, and always before deployment. Set up monitoring for automatic alerts 30 days before expiry.
OCSP stapling allows the server to cache the certificate's revocation status, speeding up TLS handshakes by eliminating the need for clients to contact the CA's OCSP responder.

Video Tutorial

Video tutorial coming soon