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Security

CSR Decoder

The CSR Decoder parses a PEM-encoded Certificate Signing Request and shows its subject fields, public key size and whether the self-signature verifies. It decodes with node-forge entirely in your browser, so the request is never transmitted to a server.

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What does a CSR decoder show?

A CSR decoder parses a PEM-encoded PKCS#10 request so its subject attributes, public-key size, and self-signature can be reviewed before it is sent to a certificate authority. This catches an incorrect common name, organization, country, damaged request, or mismatched signing operation early.

Node-forge performs the parsing and signature check entirely in the browser. The current output does not decode Subject Alternative Name or Key Usage extensions, and a valid self-signature proves only that the request was signed by its embedded key; it does not prove domain control or CA approval.