openssl x509

• openssl x509 -inform pem -noout -text
• openssl x509 -noout -dates
• openssl x509 -noout -text -in /path/to/your/cert.pem
• openssl x509 -noout -text -in /path/to/your/cert.pem | grep Validity -A2

openssl x509 -inform der -noout -text -in /path/to/cerfile.cer 
openssl x509 -inform pem -noout -text -in /path/to/cerfile.cer 

Convert from .cer to .pem

openssl x509 -inform der -in myCert.cer -out certificate.pem

Activities

• How to check certification expiration date from command line

Related commands

• openssl pkcs12
• To view .cer files
• Certificates

See also

• X.509, ASN.1, openssl x509, .pem, der, PFX, PKCS, SAN, openssl x509, CSR
• openssl [ rand | s_client | passwd | openssl req | openssl rsa | openssl genrsa | openssl x509 | openssl ca | openssl verify | openssl ec | openssl dgst | openssl pkcs12 | openssl asn1parse | openssl help | .cer to .pem, openssl version