Free SSL/TLS Checker Online

Check the validity, expiration date, and issuer of any SSL/TLS certificate online instantly. Free security diagnostic tool.

How to Use

Enter the domain name (e.g., example.com) in the input box. You can also paste a full URL.

Click the "Check SSL" button to initiate the connection.

Our server will connect to port 443 and retrieve the peer certificate details.

Review the expiration date, validity status, and issuer information.

Features

Instantly retrieves x509 SSL/TLS certificates

Calculates exact days remaining until expiration

Validates certificate chain trust (Authorized / Self-Signed)

Displays complete Subject and Issuer details

Secure API protected against SSRF

FAQ

An expired SSL certificate can immediately crash your website traffic and destroy user trust with browser security warnings. Our free online SSL Checker tool allows you to proactively diagnose TLS certificate issues in 2026 before they impact your users. Simply enter a domain name to instantly fetch its live SSL certificate data directly from our secure servers. View crucial information including the Exact Expiration Date, the issuing Certificate Authority (CA), and the cryptographic fingerprint. We even highlight whether the certificate chain is fully trusted and authorized, making it the perfect quick-check utility for sysadmins and web developers managing HTTPS deployments.

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