After you've set up your GPG key and added it to your GitHub account, you need to inform Git that there's a GPG key you'd like to use.
If you don't have a GPG key that matches your committer identity, you need to associate an email with an existing key.
If you have multiple GPG keys, you need to tell Git which one to use.
Open TerminalTerminalGit Bash.
gpg --list-secret-keys --keyid-format LONGcommand to list GPG keys for which you have both a public and private key. A private key is required for signing commits or tags.
$ gpg --list-secret-keys --keyid-format LONG
Note: Some GPG installations on Linux may require you to use
gpg2 --list-keys --keyid-format LONGto view a list of your existing keys instead. In this case you will also need to configure Git to use
git config --global gpg.program gpg2.
From the list of GPG keys, copy the GPG key ID you'd like to use. In this example, the GPG key ID is
gpg --list-secret-keys --keyid-format LONG /Users/hubot/.gnupg/secring.gpg ------------------------------------ sec 4096R/3AA5C34371567BD2 2016-03-10 [expires: 2017-03-10] uid Hubot
ssb 4096R/42B317FD4BA89E7A 2016-03-10
To set your GPG signing key in Git, paste the text below, substituting in the GPG key ID you'd like to use. In this example, the GPG key ID is
git config --global user.signingkey 3AA5C34371567BD2