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SSL Certificate (PEM)
Paste the certificate you received from your Certificate Authority.
Private Key (PEM)
Paste the private key that was generated alongside your CSR.
Certificate Details
- Common Name (CN)
- -
- Expires
- -
Why Check for a Mismatch?
If you install an SSL certificate with the wrong private key, your web server will fail to start or throw a TLS handshake error. Browsers will show a connection error instead of loading your site.
A mismatch happens when the private key was not generated as part of the same CSR that was used to request the certificate. This can occur when:
- The certificate was re-issued with a new CSR but the old private key was kept.
- Files were renamed or accidentally swapped during installation.
- Multiple certificates are managed and the wrong files were combined.
Run this check before every installation to catch mismatches instantly - before they cause downtime.
Need to Generate a New SSL Certificate?
Generate a free, trusted SSL certificate powered by Let's Encrypt - completely free.