CSR Decoder - View Certificate Signing Request Details

Decode CSR files to view subject, public key, and signature details. Verify CSR content before submitting to certificate authority. Browser-based.

CSR Input

Paste CSR (PEM format)

Decoded Information

Paste a CSR to decode

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Frequently Asked Questions

A Certificate Signing Request (CSR) is a message sent to a Certificate Authority to apply for an SSL/TLS certificate. It contains your public key and identity information.

Subject name (Common Name, Organization, Country, etc.), public key details, key algorithm, key size, and a digital signature proving you have the private key.

To verify the information is correct. Typos in domain names or organization details will appear in your certificate. Check before paying for a certificate.

Standard PEM-encoded CSRs starting with -----BEGIN CERTIFICATE REQUEST----- or -----BEGIN NEW CERTIFICATE REQUEST-----.

Yes. All decoding happens in your browser. CSR content never leaves your device. However, CSRs are meant to be shared with CAs anyway.

No. The CSR only contains the public key. Your private key should never be shared or included in a CSR.

RSA key sizes (2048, 4096 bits) and EC curve names (P-256, P-384) are displayed. 2048-bit RSA or 256-bit EC are minimum recommended.

SANs (multiple domain names) are extracted and displayed if present in the CSR. All listed domains will be covered by the certificate.

Use OpenSSL: openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr. This tool only decodes existing CSRs.

The CSR may be corrupted or improperly formatted. Try regenerating it. Ensure you copy the entire PEM block including headers.

CSR Input

Decoded Information

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