A CSR may be represented Base64; an example of which is given below:

-----BEGIN CERTIFICATE REQUEST-----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-----END CERTIFICATE REQUEST-----

Don't have a CSR? Then Click here

Want SHA256 -default Signature Algorithm is sha256WithRSAEncryption Click here

How to view a CSR using openssl:

openssl req -noout -text -in server.csr