SSL Certificate Checker
Verify the SSL/TLS certificate of any website. Ensure your connection is secure and your data is protected.
SSL checks provide information based on current certificate status. For critical applications, always verify with the certificate authority.
SSL (Secure Sockets Layer) and TLS (Transport Layer Security) certificates are digital certificates that authenticate a website's identity and enable an encrypted connection. They are essential for securing online communications, protecting sensitive data like login credentials, payment information, and personal details from being intercepted by malicious actors. Our SSL Checker tool helps you verify these certificates quickly and easily.
SSL/TLS certificates are crucial for website security and user trust. Our SSL Checker tool helps you verify and monitor these certificates effectively. With our tool, you can:
Verify Certificate Validity: Quickly check if an SSL certificate is current, expired, or misconfigured.
Enhance Security Awareness: Understand the security level of websites you interact with or manage.
Prevent Browser Warnings: Ensure your website doesn't trigger "Not Secure" warnings, which can deter visitors.
Check Issuer Information: Identify the Certificate Authority (CA) that issued the certificate.
Inspect SANs: View all Subject Alternative Names covered by the certificate.
Monitor Expiration Dates: Keep track of when certificates need renewal to avoid service disruptions.
Detailed Connection Info: Check TLS version, cipher suite, and security strength.
Real-time Validation
SSL/TLS certificate validation for any domain and port.
Comprehensive Details
Subject, Issuer, Serial Number, Version.
Validity Period
Includes days until expiration with progress bar.
SANs Listing
Subject Alternative Names (SANs) listing.
Certificate URIs
OCSP, CA Issuers, CRL Distribution Points.
Connection Details
TLS/SSL Protocol, Cipher Suite, Cipher Strength, and Security Level.
User-Friendly & Responsive
Clear, categorized results, for desktop and mobile.
Website Owners & Admins
To regularly verify and maintain their website's SSL certificate health.
IT & System Administrators
For routine checks, audits, and monitoring SSL certificates.
Security Professionals
To assess and validate SSL certificate configurations in audits.
Web Developers
To ensure SSL certificates are correctly implemented.
Curious Internet Users
To check the security status of websites they visit.
When you check an SSL certificate using our tool, you receive detailed information about the certificate's properties and status. Here's what each detail means:
Subject: Information about the entity the certificate was issued to (e.g., domain name, organization).
Issuer: The Certificate Authority (CA) that issued the SSL certificate. CAs are trusted entities that verify the identity of the certificate requester.
Serial Number & Version: Unique identifiers for the certificate.
Valid From / Valid To: The date range during which the certificate is valid. After the "Valid To" date, the certificate expires and needs to be renewed.
Days Until Expiration: The number of days remaining until the certificate expires. It's important to renew the certificate before it expires to maintain a secure connection.
Subject Alternative Names (SAN): Additional domain names or IP addresses that the SSL certificate covers. This is useful for securing multiple domains with a single certificate.
OCSP URIs, CA Issuers, CRL Distribution Points: URLs related to certificate status checking and chain validation.
TLS Version & Cipher Suite: Details about the secure connection parameters established with the server.
Cipher Strength & Security: An indication of the connection's encryption strength.
For a deeper understanding of SSL certificates, consider exploring resources on web security and SSL/TLS technology.
Check Subdomains: Remember to check SSL certificates for all critical subdomains (e.g., www., mail., shop.). A wildcard certificate (*.example.com) or a multi-domain (SAN) certificate can cover these.
Check Non-Standard Ports: Use the port input field to check SSL/TLS on services running on ports other than 443 (e.g., secure email servers, custom applications).
Understand Certificate Chains: An SSL certificate is typically part of a chain of trust: Root CA -> Intermediate CA -> Your Domain Certificate. Ensure the full chain is correctly installed on your server.
CAA Records: Consider setting up DNS Certification Authority Authorization (CAA) records to specify which CAs are authorized to issue certificates for your domain, adding an extra layer of security.
HTTP Strict Transport Security (HSTS): Implement HSTS to instruct browsers to only connect to your site via HTTPS, preventing downgrade attacks.
Regular Audits: Beyond simple checks, perform comprehensive SSL/TLS server configuration audits using tools like SSL Labs' SSL Test to identify vulnerabilities.
Automate Renewals: Where possible, use automated certificate renewal processes (e.g., with Let's Encrypt and Certbot) to avoid accidental expirations.
Let's Encrypt Documentation - Learn about free, automated, and open SSL/TLS certificates.
Qualys SSL Labs Server Test - A comprehensive free online service to test the SSL/TLS configuration of any web server.
MDN Web Docs: Transport Layer Security (TLS) - Detailed information about TLS and web security.
Understanding CAA Records - Learn more about Certification Authority Authorization.