How to extract the public key from a DH key file using OpenSSL "pkey" command?

If you want to extract the public key out from a DH key file (private key an public key), you can use the OpenSSL "pkey -pubout" command as shown below:

C:\Users\fyicenter>\local\openssl\openssl.exe

OpenSSL> pkey -in my_dh.key -pubout -out my_dh_pub.key
OpenSSL> exit

C:\Users\fyicenter>type my_dh_pub.key
-----BEGIN PUBLIC KEY-----
MIIBHzCBlQYJKoZIhvcNAQMBMIGHAoGBALzizRYfhhdc1miJMXG88tKCCdLOSIG7
G2Fsh27ec41AP+pExiT781P/JjnLmy85Niy9OhTZDkiSnAqNiWO+DC/3elIKjHfx
QgBMMd+57MCduH9MEOVEQKb/drJkPFeCBShJlM+KyoNCpLfV0Tu/icb/KTQAUdiQ
A0cehBtTNmwzAgECA4GEAAKBgCoDjDV/cvxDi0PC9h8iiqD+i5gzQNnoe3jd77RK
HW2pZ39jDvYEGtfgWsg8TAw2vyNCKZcxP3ho2BRMF4X7J7PTwijMFMHQbcGzyY1R
WmcCO4UfkRYVN65NtiA3zmu7hBaiIYF4VgpoFcOlUcsUlNceaRS6zc5ua0GGNMpA
DThf
-----END PUBLIC KEY-----

Options used in this command are:

• "-in my_dh.key" - Read the DH key file from: C:\Users\fyicenter\my_dh.key
• "-pubout" - Extract the public key out of the DH key file
• "-out my_dh_pub.key" - Save the public key in a file with no password protection.

⇒ OpenSSL "pkey -pubin" - View DH Public Key

⇐ OpenSSL "pkey -text" - Print DH Key in Text

⇑ OpenSSL "genpkey" Command for DH Keys

⇑⇑ OpenSSL Tutorials