Certificate signing request decoder
Inspect a pasted CSR and display subject and public key fields.
How to use Certificate signing request decoder
Certificate signing request decoder reads a PEM-encoded PKCS#10 CSR and lists its subject fields, such as CN and O, together with the RSA public key size in bits and whether the request's signature verifies. Paste text beginning with -----BEGIN CERTIFICATE REQUEST-----, under 100 KB. A valid signature does not establish identity or certificate trust.
- Paste the source into the input editor, or load the built-in example.
- Check the source format before running the operation.
- Run certificate signing request decoder, review the output, then use the available copy or download controls.
What this tool supports
Inspect a pasted CSR and display subject and public key fields.
Limits and processing
CSV/XLSX inputs are capped at 10 MB each, 200 columns and 20,000 rows; joined output is capped at 20,000 rows. JSONPath script/filter evaluation is disabled. Other operations apply their visible controls and text limits.
Example source
-----BEGIN CERTIFICATE REQUEST----- MIICWzCCAUMCAQAwFjEUMBIGA1UEAxMLZXhhbXBsZS5jb20wggEiMA0GCSqGSIb3 DQEBAQUAA4IBDwAwggEKAoIBAQC7L3QuAYdWgOXXK7dhMIqzpLmdHQwEXYwjq1yd mhBS+kkFc1/SsDxOoW/ycR8XorXX0P9WuKxc44hW2QP+LwgiAJwXnzC8CYX9YXl0 ujSJhYAD9FLfdrMCW2RErfa18XYCZ0Kk0Z5+ptD9IkKRI/YKbjN0tAd0DGioLvmV hEYQQZiRI9ux9Y+DxH0Mz99awTvxa6Xr/YHuKpTAH+15bpmUZHrj1GxUMLKyPjck v8B2fXvS9wjH24zm/TaqCZt/ZD9bwMCFw49nmI1XnJgw7hlyuQfF1/MNpq1QWp6g tZuWxrN6J761587g+aQdSZwHcUDeZ4JYaRAj/IwiXyZjn+f1AgMBAAGgADANBgkq hkiG9w0BAQsFAAOCAQEAf3z0ZW192ZnDf2Q5K6HCbLyVB5iJm0djHGa60jMZS5BI T221i46aQW5rsgruyMkkfKGXlUlr/ojbTtCzzQkw4zSyhDI2pDMv7WcIxhAqHbZZ 3RVksxk3TvvqljhPSap1htXpZe12iGcYbCrgFO3jWz5/TGH7rn8nM/7cDdxRvQ3s YA4Ru9tabB5DHyY+B0kYJuKK4hSzvgIspF8+OAxDE4vml5J7tHq0g3BxomE+85qx yhZEItgZkN+nG15UsDAQXmGxNZ7sCtitDFgy7ttgrYaOgFcXEaRK+IJFPjOpeuGn 7knKj0UZIPEvYWm/1BJpjy349V0uOpHIFalpY0ciWQ== -----END CERTIFICATE REQUEST-----
Frequently asked questions
Does the CSR decoder support ECDSA keys?
No. Only RSA requests are decoded; a CSR with an elliptic-curve or other key type returns an error asking for a supported RSA PEM certificate signing request. The key size shown is the RSA modulus length in bits.
What does Signature valid mean in the CSR decoder?
It shows whether the CSR's self-signature verifies with the public key it contains, checked through the browser's Web Crypto API. True means the request is internally consistent; it does not prove who created it or that a certificate authority will trust it.
Why is my CSR rejected even though it looks correct?
The text must start with the exact line -----BEGIN CERTIFICATE REQUEST-----. Requests using the older NEW CERTIFICATE REQUEST label, binary DER files and inputs over 100 KB are rejected; change both header lines to the standard label and try again.
Where is my input processed?
This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.
What are the input limits?
CSV/XLSX inputs are capped at 10 MB each, 200 columns and 20,000 rows; joined output is capped at 20,000 rows. JSONPath script/filter evaluation is disabled. Other operations apply their visible controls and text limits.