SSL/TLS Certificate Health Checker

Certificate expiry · TLS version · HSTS · CAA · cipher strength — instant A–F grade

Domain

TLS handshake performed server-side via the Next.js API route

What gets checked

Certificate

Expiry date, issuer, key size, SANs, self-signed detection

TLS version

TLS 1.3 / 1.2 / 1.1 / 1.0 — flags deprecated versions

Cipher suite

Cipher name and key strength — flags weak ciphers

HSTS

Header presence, max-age, includeSubDomains, preload flag

CAA records

Which CAs are authorised to issue certificates for this domain

Chain trust

Whether the certificate chain is trusted by system roots