Bitcoin Forum

Is there a good offline open source linux cli tool I can run to generate a key pair on air gapped computer?  (not sure where to post as is not hw wallet, but seeking offline method for key pair generation)

Have you tried Pywallet? You can generate wallets with it: https://github.com/ranaroussi/pywallet

You can also check Bitaddress if you don't mind dealing with UI based solutions: https://github.com/pointbiz/bitaddress.org

You can use Electrum wallet on an airgapped device instead. You can also use iancoleman html file on an airgapped device instead too.

https://electrum.org/
https://electrum.readthedocs.io/en/latest/coldstorage.html

https://github.com/iancoleman/bip39/releases/latest/If you are not convenient with only seed phrase, you can include passphrase which will generate you different keys and addresses.

For electrum cold storage wallet, to make it a paper wallet, no need for watch-only wallet. Watch-only wallet is needed for making unsigned transaction and for broadcasting of transaction signed on the cold storage wallet. You can delete the cold wallet after you have created it on an airgapped device and after you backup the seed phrase and passphrase differently in different locations.

How about doing it manually instead of using the CLI tool to generate a key pair?
Have you heard that you can generate a key pair by using a coin?

If not, then it should be the best where you can randomly generate a unique private key from Coin Flipping.

We have a guide on the forum on how to do that check this link below

- https://bitcointalk.org/index.php?topic=3222335.0

Once you've done generating a binary convert it to a hex and then use the bitaddress as suggested above and run it offline and convert the hex to the Wif key and public key.

WIF key should be supported to any wallet like Bitcoin core or Electrum.