CSR Decoder

Decode Certificate Signing Request details

About CSR Decoder

Our free CSR Decoder parses Certificate Signing Requests in PEM format and displays all fields in a clear, human-readable layout. View the subject, public key algorithm and size, requested SANs, and all CSR attributes. Perfect for verifying CSR contents before submitting to a Certificate Authority.

How to Use

1Copy your CSR in PEM format (with BEGIN/END markers).
2Paste it into the text area above.
3Click "Decode" to parse and display subject, key, and attribute fields.
4Review the decoded fields before submitting to your CA.

Use Cases

•Verify CSR fields before sending to a Certificate Authority
•Confirm SANs are correctly included in the request
•Check key algorithm and size meet security requirements
•Debug CSR generation issues across different tools

Frequently Asked Questions

The CSR must be in PEM format with -----BEGIN CERTIFICATE REQUEST----- and -----END CERTIFICATE REQUEST----- markers.

Yes. The decoded output includes the public key algorithm, key size, and the key itself.

Yes. If your CSR includes Subject Alternative Names, they will be decoded and displayed.

No. CSRs are processed securely and never stored or logged after decoding.

Tips & Best Practices

•Decode CSRs before submitting to Certificate Authorities
•Verify CSR contains correct domain names and organization details
•Check CSR key size and algorithm meet security requirements
•Keep decoded CSR information for certificate request records

Technical Details

Format: PKCS#10 CSR format parsing and analysis
Fields: Subject, public key, signature algorithm, extensions
Validation: CSR structure and content validation
Output: Complete CSR details in human-readable format