Free Online SSL Certificate Checker

What is an SSL/TLS Certificate?

An SSL/TLS (Secure Sockets Layer / Transport Layer Security) certificate is a digital certificate that authenticates a website's identity and enables an encrypted connection. It's a crucial component for securing online communication and protecting sensitive data exchanged between a user's web browser and the website's server. Websites using SSL/TLS typically display "HTTPS" in the URL and a padlock icon in the browser bar. This online SSL checker helps view some details of these certificates.

Why Check an SSL Certificate?

• Verify Website Identity: Confirm that the certificate is issued to the correct domain and by a trusted Certificate Authority (CA).
• Check Validity Period: Ensure the certificate is current and not expired, and see when it's due for renewal. Our tool helps check SSL certificate validity.
• Inspect Certificate Chain: Understand the chain of trust from the end-entity certificate up to a trusted root CA.
• View Subject Alternative Names (SANs): See all domain names and subdomains covered by the certificate.
• Troubleshooting Connection Issues: Help diagnose SSL/TLS related errors or warnings users might encounter.
• Security Auditing: As part of a security assessment, review certificate details and issuance history via an SSL/TLS certificate lookup.

How Our Online SSL Checker Works

• Enter Domain: Input the domain name (e.g., `example.com`) you want to check. Do not include `http://` or `https://`.
• Fetch Information: Click "Check Certificate Info." Our tool queries the CertSpotter API, which monitors public Certificate Transparency (CT) logs.
• View Issued Certificates: The tool will display a list of SSL/TLS certificates that have been publicly logged as issued for the domain. For each, it shows:
  • Common Name (CN) and Subject Alternative Names (SANs) covered.
  • Issuer information.
  • Validity period (Not Before, Not After dates).
  • An indicator of current validity status (Valid, Expired, Expiring Soon).
• Download Report: You can download a summary of the retrieved certificate issuance information.

Important Note: This tool checks Certificate Transparency logs for *issued* certificates. It does not perform a live connection test to the domain's server to verify the *currently serving* certificate or its full configuration (like SSL Labs does). For a complete server security test, use a comprehensive tool like SSL Labs' SSL Test.