Note: in these examples the '\' means the example should be all on one line.
Display the contents of a certificate:
openssl x509 -in cert.pem -noout -text
Display the certificate serial number:
openssl x509 -in cert.pem -noout -serial
Display the certificate subject name:
openssl x509 -in cert.pem -noout -subject
Display the certificate subject name in RFC2253 form:
openssl x509 -in cert.pem -noout -subject -nameopt RFC2253
Display the certificate subject name in oneline form on a terminal supporting UTF8:
openssl x509 -in cert.pem -noout -subject -nameopt oneline,-esc_msb
Display the certificate MD5 fingerprint:
openssl x509 -in cert.pem -noout -fingerprint
Display the certificate SHA1 fingerprint:
openssl x509 -sha1 -in cert.pem -noout -fingerprint
Convert a certificate from PEM to DER format:
openssl x509 -in cert.pem -inform PEM -out cert.der -outform DER
Convert a certificate to a certificate request:
openssl x509 -x509toreq -in cert.pem -out req.pem -signkey key.pem
Convert a certificate request into a self signed certificate using extensions for a CA:
openssl x509 -req -in careq.pem -extfile openssl.cnf -extensions v3_ca \
-signkey key.pem -out cacert.pem
Sign a certificate request using the CA certificate above and add user certificate extensions:
openssl x509 -req -in req.pem -extfile openssl.cnf -extensions v3_usr \
-CA cacert.pem -CAkey key.pem -CAcreateserial
Set a certificate to be trusted for SSL client use and change set its alias to "Steve's Class 1 CA"
openssl x509 -in cert.pem -addtrust clientAuth \
-setalias "Steve's Class 1 CA" -out trust.pem