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SSL Checker

Check SSL certificate information for any domain. View TLS version info, certificate details, and security recommendations. Educational tool for understanding SSL/TLS.

🔒 HTTPS Status

Enter a domain

Check if the site supports HTTPS

🔑 TLS Version

Transport Layer Security version

📝 Certificate

Certificate validity status

🔭 HSTS

HTTP Strict Transport Security

📄 Certificate Details (Simulated)

Subject -

Issuer -

Valid From -

Valid Until -

Serial Number -

Signature Algorithm SHA-256 with RSA

SSL 3.0

Deprecated

TLS 1.0

Deprecated

TLS 1.1

Legacy

TLS 1.2

Secure

TLS 1.3

Recommended

SSL/TLS Security Best Practices

Always use TLS 1.2 or higher - disable older versions
Enable HSTS (HTTP Strict Transport Security) to force HTTPS
Use certificates with at least 2048-bit RSA keys
Keep certificates renewed before expiration
Implement OCSP Stapling for better performance
Use strong cipher suites and disable weak ones
Enable certificate transparency monitoring

🛈 Important: This tool provides educational information about SSL/TLS based on browser capabilities and simulated data. For comprehensive SSL testing including detailed cipher suite analysis, vulnerability scanning, and complete certificate chain validation, use server-side tools like Qualys SSL Labs or test from a server environment.

About SSL Checker

This educational tool helps you understand SSL/TLS certificates and HTTPS configuration. SSL (Secure Sockets Layer) and its successor TLS (Transport Layer Security) are cryptographic protocols that provide secure communication over a computer network. They are essential for protecting sensitive data transmitted between web browsers and servers.

How to Use

Enter a domain name in the input field (e.g., "example.com").
Click Check SSL to simulate an SSL check.
Review the HTTPS status, TLS version, and certificate information.
Check the Certificate Details section for simulated certificate data.
Review the TLS Versions to understand which versions are secure.
Follow the Security Best Practices recommendations.

Frequently Asked Questions

What is the difference between SSL and TLS?

SSL (Secure Sockets Layer) is the older protocol, with versions 1.0, 2.0, and 3.0. TLS (Transport Layer Security) is the newer, more secure successor with versions 1.0, 1.1, 1.2, and 1.3. TLS 1.3 is the current recommended version. The terms are often used interchangeably, but modern systems use TLS.

Why can't this tool perform full SSL checks?

Browsers restrict JavaScript from directly accessing low-level SSL certificate information for security reasons. Full SSL testing requires server-side tools that can establish raw TLS connections and analyze certificate chains, cipher suites, and protocol versions at the network level.

What is HSTS and why is it important?

HSTS (HTTP Strict Transport Security) is a security feature that tells browsers to always use HTTPS connections for a domain, preventing downgrade attacks and cookie hijacking. Once a browser receives an HSTS header, it will automatically upgrade HTTP requests to HTTPS for the specified duration.

How often should SSL certificates be renewed?

SSL certificates typically have validity periods ranging from 3 months to 2 years. Let's Encrypt certificates are valid for 90 days. It's recommended to automate renewal and monitor certificate expiration. Most CAs send renewal reminders 30, 14, and 7 days before expiration.

What makes a certificate trustworthy?

A certificate is trustworthy when it's issued by a trusted Certificate Authority (CA) that's included in major browser and operating system trust stores, hasn't expired, hasn't been revoked, is used on the correct domain, and has a valid certificate chain to a root CA.