SSL Lookup

What is an SSL Lookup Tool?

An SSL Lookup Tool is an online or command-line tool that retrieves and analyzes details about an SSL/TLS certificate for a given website or domain. It helps verify whether a website has a valid and properly configured SSL certificate, which is essential for secure communication over HTTPS.

How Does SSL Lookup Work?

When you enter a domain into an SSL lookup tool, it performs the following steps:

1. Connects to the Website's Server

   • Establishes an SSL/TLS handshake with the server.
   • Requests the SSL certificate associated with the domain.

2. Extracts SSL Certificate Information

   • Displays key details such as:
     • Issuer (Certificate Authority, CA) – e.g., Let's Encrypt, DigiCert, GlobalSign.
     • Validity Period – Start and expiration dates.
     • Domain Name Matching – Checks if the certificate matches the requested domain.
     • Encryption Strength – Information about algorithms used (e.g., RSA, ECDSA).

3. Checks Certificate Validity

   • Confirms if the certificate is trusted by browsers.
   • Checks for expired or revoked certificates.
   • Verifies the certificate chain to ensure proper authentication.

Why Use an SSL Lookup Tool?

1. Security Verification

   • Ensures a website has a valid and properly issued SSL certificate.
   • Detects self-signed or expired certificates that could pose security risks.

2. Troubleshooting SSL Issues

   • Helps diagnose SSL/TLS errors like "Certificate Not Trusted" or "Expired Certificate."

3. Checking HTTPS Implementation

   • Confirms if a website enforces HTTPS properly.
   • Useful for web admins and developers.

4. Identifying Certificate Authority (CA)

   • Finds out which CA issued a website’s certificate.
   • Helps check for certificates issued by untrusted or compromised CAs.

5. Detecting Fraudulent or Fake Certificates

   • Phishing sites sometimes use fake or invalid SSL certificates.
   • SSL lookup helps identify suspicious certificates.

Common SSL Issues Found via SSL Lookup

• Expired Certificates – Causes security warnings in browsers.
• Mismatched Domain Names – Certificate does not match the requested domain.
• Self-Signed Certificates – Not trusted by browsers unless manually added.
• Revoked Certificates – The CA has invalidated the certificate due to security reasons.
• Weak Encryption Algorithms – Older or insecure SSL/TLS versions used.

An SSL Lookup Tool is essential for checking a website’s SSL certificate details, verifying security, and troubleshooting SSL-related issues. It helps ensure websites are secure, properly encrypted, and compliant with HTTPS standards.