CSR Decoder

What's inside a CSR

A Certificate Signing Request bundles your organization's identifying details (domain name, company, location) together with a public key, ready to hand to a Certificate Authority so they can issue a signed certificate back to you. Decoding it lets you double-check those details are correct - a typo in the Common Name or Organization field before submitting to a CA can mean paying for a reissue later.

A straight field-by-field readout

This tool is built specifically around showing exactly what's encoded in a CSR as a clean table - every subject field, the key type, and key size, laid out plainly for a quick final review before you submit the CSR to a Certificate Authority. If you also want a pass/fail validity verdict on whether the CSR actually parses correctly, the companion CSR Checker tool adds that validity badge on top of a similar field breakdown.

Catching mistakes before they cost a reissue

Certificate Authorities will issue exactly what the CSR specifies - a misspelled domain in the Common Name field produces a certificate for that misspelled domain, not the one you actually intended. Reviewing the decoded fields catches this class of mistake before submission, rather than after paying for and waiting on an incorrect certificate.

Why optional fields sometimes don't appear

Only the fields that were actually included when the CSR was originally created will appear in the decoded output - State, Organization, and similar fields are often optional depending on the certificate type being requested, so their absence here usually just reflects how the CSR was generated, not a decoding problem.

الأسئلة الشائعة

Is my CSR uploaded or stored anywhere?

It's only used to decode the fields for this one request and isn't saved afterward. A CSR doesn't contain your private key, so it's safe to paste into tools like this.

Why don't I see a State or Organization field in the result?

Only the fields that were actually included when the CSR was created will appear - optional fields left blank at creation time simply won't show up here.

How is this different from the CSR Checker tool?

This tool focuses on a clean, direct field-by-field decode of exactly what's in the CSR. The CSR Checker additionally gives a pass/fail validity verdict confirming the CSR is well-formed, alongside a similar field breakdown.

What should I check for in the decoded output before submitting to a CA?

Verify the Common Name exactly matches the domain you want the certificate for, and double-check Organization and other identifying fields for typos - mistakes here mean the issued certificate will be wrong too.

Can this decode a CSR for any key type?

Yes - both RSA and elliptic-curve (EC) key types are decoded, showing the key type and bit length alongside the subject fields.