paperkey — An OpenPGP key archiver. More information: <https://www.jabberwocky.com/software/paperkey/>.

Take a specific secret key and generate a text file with the secret data

paperkey --secret-key {{path/to/secret_key.gpg}} --output {{path/to/secret_data.txt}}

Take the secret key data in `secret_data.txt` and combine it with the public key to reconstruct the secret key

paperkey --pubring {{path/to/public_key.gpg}} --secrets {{path/to/secret_data.txt}} --output {{secret_key.gpg}}

Export a specific secret key and generate a text file with the secret data

gpg --export-secret-key {{key}} | paperkey --output {{path/to/secret_data.txt}}