SSL certificate checker
Check any site's SSL/TLS certificate: issuer, expiry date, days remaining, chain trust, and the names it covers.
Check a site's SSL certificate
Inspects the certificate on port 443. We read the chain only; we never store certificates or connect to private addresses.
Expired certificates break trust
A web certificate proves a site's identity and encrypts traffic. When one expires or fails to validate, browsers show warnings and captive-portal logins stop working. This checker performs a live TLS handshake and reports exactly what the certificate says.
What this tool gives you
- Issuer, subject, validity window, and the number of days until expiry.
- Chain-trust result, TLS protocol version, and all subject alternative names.
- A safe, read-only check that never inspects private or internal addresses.
Related WiFi tools
Trusted guest WiFi by default
An expired certificate breaks captive-portal sign-in and erodes trust. Purple manages portal certificates and HTTPS for you, so logins stay secure across every site.
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