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SSL Checker

Check SSL certificate details for any domain online for free. Verify expiry, issuer, and security status instantly to keep your site secure.

Common Questions

Frequently Asked Questions

Everything you need to know about using our SSL Checker

SSL Checker - Frequently Asked Questions

What SSL certificate details are shown?

View issuer (CA), validity dates, certificate chain, encryption strength (256-bit), supported protocols (TLS 1.2/1.3), and any errors or warnings. Full SSL/TLS analysis for any domain.

How do I know if my SSL certificate is expiring?

Enter your domain to see exact expiry date and days remaining. We show 'Valid', 'Expiring Soon' (30 days), or 'Expired' status with color coding. Set calendar reminders based on this date.

Can I check if a site has proper SSL security?

Yes! We verify: certificate trust chain, hostname matches, no weak ciphers, proper HSTS headers, and TLS 1.2+ support. Red/green indicators show security health at a glance.

What's the difference between SSL and TLS?

TLS is the modern successor to SSL. TLS 1.2 and 1.3 are current standards. 'SSL' is still commonly used to mean both. Our checker looks for TLS certificates (true modern security).

About This Tool

What It Does

Check SSL/TLS certificates for any domain online for free. Our SSL checker validates certificate chains, verifies expiration dates, tests encryption strength, and identifies configuration vulnerabilities. Perfect for web developers launching new sites, DevOps engineers monitoring production certificates, and security auditors assessing HTTPS implementations. Get detailed reports with remediation recommendations.

Technology

How It Works

Enter any domain name (e.g., example.com). The tool connects via HTTPS and retrieves the full certificate chain: server certificate, intermediate certificates, and root CA. Checks: expiration date, issuer identity, SAN coverage, TLS version support (1.0-1.3), cipher suites, HSTS headers, and OCSP status. Vulnerabilities like expired certs, weak ciphers, and mismatched hostnames are flagged with severity levels.

Popular Uses

Common Use Cases

1

Pre-launch checks - validate SSL setup before deploying new websites and apps

2

Certificate monitoring - track expiration dates and receive alerts before renewal

3

Security audits - identify weak ciphers, outdated TLS versions, and misconfigurations

4

Vendor assessment - verify third-party APIs and webhooks have proper SSL certificates

5

Compliance - confirm HTTPS meets PCI DSS, HIPAA, and SOC 2 certificate requirements

Compatibility

Supported Formats

Domain nameURLIP address
Comparison

How We Compare

FeatureKeynouSSL LabsDigiCert
PriceFreeFreeFree/Premium
No SignupYesYesNo
TLS 1.3 CheckYesYesYes
Remediation TipsYesLimitedYes
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