Certificate Key Matcher
Paste your SSL certificate and private key to verify they are a matching pair. Mismatched keys cause SSL handshake errors on your server.
Frequently Asked Questions
Why does certificate and key mismatch happen?
A mismatch usually happens when a new certificate is issued but installed with an old private key, or when the wrong certificate file is used. The certificate must be issued for the specific private key used to generate the CSR.
Is my private key secure if I paste it here?
The check runs entirely server-side using PHP OpenSSL. Your private key is never logged or stored. However for maximum security, use a local tool like OpenSSL: openssl x509 -noout -modulus -in cert.pem | md5sum and compare with: openssl rsa -noout -modulus -in key.pem | md5sum
What happens if they do not match?
Your web server will fail to start or throw an SSL handshake error. Visitors will see certificate warnings. Fix by obtaining a new certificate with a CSR generated from your actual private key.