SSL/TLS certificate checker
Check a site's certificate: expiry, issuer and TLS version. Free, no signup.
Never get caught by an expired certificate
WWT checks your certificate, TLS version, uptime, domain expiry and email security every day and warns you well before anything breaks. Free, no credit card.
Start monitoring freeAbout SSL/TLS certificates
What is an SSL/TLS certificate?
An SSL/TLS certificate proves a website's identity and encrypts traffic between the browser and the server. Without a valid one, browsers show a security warning.
Why does certificate expiry matter?
When a certificate expires, every visitor gets a security warning and HTTPS breaks - often on a weekend or holiday. Renewing in time avoids outages and lost trust.
Which TLS versions are safe?
Modern best practice is TLS 1.2 and 1.3 only. TLS 1.0 and 1.1 are deprecated and considered insecure.
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