If you don't have an existing GPG key, you can generate a new GPG key to use for signing commits and tags.

Supported GPG key algorithms

GitHub supports several GPG key algorithms. If you try to add a key generated with an unsupported algorithm, you may encounter an error.

  • RSA
  • ElGamal
  • DSA
  • ECDH
  • ECDSA
  • EdDSA

Generating a GPG key

Note: Before generating a new GPG key, make sure you've verified your email address. If you haven't verified your email address, you won't be able to sign commits and tags with GPG.

  1. Download and install the GPG command line tools for your operating system.
  2. Open TerminalTerminalGit Bash.

  3. Paste the text below to generate a GPG key pair.

    $ gpg --gen-key
    
  4. At the prompt, specify the kind of key you want, or press Enter to accept the default RSA and RSA.

  5. Enter the desired key size. We recommend the maximum key size of 4096.
  6. Enter the length of time the key should be valid. Press Enter to specify the default selection, indicating that the key doesn't expire.
  7. Verify that your selections are correct.
  8. Enter your user ID information.

    Note: When asked to enter your email address, ensure that you enter the verified email address for your GitHub account.

  9. Type a secure passphrase.

  10. Use the gpg --list-secret-keys --keyid-format LONG command 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 LONG to view a list of your existing keys instead. In this case you will also need to configure Git to use gpg2 by running git config --global gpg.program gpg2.

  11. From the list of GPG keys, copy the GPG key ID you'd like to use. In this example, the GPG key ID is 3AA5C34371567BD2:

    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
    
  12. Paste the text below, substituting in the GPG key ID you'd like to use. In this example, the GPG key ID is 3AA5C34371567BD2:

    gpg --armor --export 3AA5C34371567BD2
    # Prints the GPG key ID, in ASCII armor format
    
  13. Copy your GPG key, beginning with -----BEGIN PGP PUBLIC KEY BLOCK----- and ending with -----END PGP PUBLIC KEY BLOCK-----.

  14. Add the GPG key to your GitHub account.

Further reading