Free Tool

SSL Certificate Checker

Instantly check any website's SSL certificate. See expiration dates, issuer details, TLS version, and more. Free, no signup required.

What You Get

Here's an example of the SSL certificate details this tool reveals. Try it above with any domain.

A

SSL Certificate Valid

example.com — Expires in 82 days

Subject*.example.com
IssuerLet's Encrypt R3
TLS ProtocolTLSv1.3
Key Size2048 bits
Valid FromJan 15, 2026
Valid UntilApr 15, 2026
Browser TrustedYes
HSTS EnabledYes

The SSL grade is calculated from your TLS protocol version, key strength, and certificate validity. A grade of A means the site uses TLS 1.3 with a strong key and the certificate is not close to expiring. Lower grades indicate outdated protocols like TLS 1.0 or 1.1, weak key sizes, or certificates nearing expiration.

The checker also verifies whether the certificate is trusted by browsers, confirms the domain name matches the certificate subject, and inspects the full certificate chain from the server certificate through intermediates to the root CA. HSTS (HTTP Strict Transport Security) is checked to ensure browsers are forced to use HTTPS, preventing downgrade attacks.

How It Works

1

Enter Domain

Type any domain name or URL. We'll extract the hostname automatically.

2

We Check the Certificate

Our server connects via TLS and retrieves the full SSL certificate chain.

3

See the Results

View certificate validity, issuer, expiration, TLS protocol, and fingerprint instantly.

Frequently Asked Questions

This tool connects to any website and retrieves its SSL/TLS certificate details. It shows you the certificate validity, issuer, expiration date, days until expiry, TLS protocol version, and fingerprint — all in real time.

Yes, completely free with no signup required. Just enter a domain and check instantly. There are no daily limits.

An SSL (Secure Sockets Layer) certificate is a digital certificate that authenticates a website's identity and enables an encrypted connection. When you see the padlock icon in your browser, that means the site has a valid SSL certificate.

You should check your SSL certificate at least monthly, or whenever you make changes to your server configuration. For continuous monitoring, exit1.dev offers automated SSL monitoring that checks your certificates with every uptime check and alerts you before they expire.

This shows how many days remain before your SSL certificate expires. Most certificates are valid for 90 days (Let's Encrypt) or 1 year. You should renew before expiration to avoid browser security warnings that will scare away your visitors.

Common reasons include: the certificate has expired, the certificate was issued for a different domain, the certificate chain is incomplete, or the certificate was issued by an untrusted authority. Check the error message for specific details.

TLS 1.2 and TLS 1.3 are considered secure. TLS 1.0 and 1.1 are deprecated and should not be used. TLS 1.3 is the latest version and offers the best security and performance.

Yes! exit1.dev includes automatic SSL monitoring with every website you monitor. You'll get alerts before certificates expire — no manual checking needed. It's included free with all plans.

Learn More About SSL Certificates

Guides and best practices for managing SSL certificates and keeping your sites secure.

How to Check an SSL Certificate

Complete guide to verifying SSL certificates using browsers, command line, and online tools.

SSL Certificate Errors Explained

Every SSL error your browser can throw — what causes it and how to fix it fast.

Free SSL Certificate Monitoring

Set up automated SSL monitoring with alerts before your certificates expire.

SSL Expiration: The Other Deadline

Why SSL certificate expiry deserves the same attention as domain expiration.

Need Continuous SSL Monitoring?

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