Bip39 Seed Generator. The passphrase just isn't chosen from the predefined list of 2048 words – it can be any word or phrase you choose. BIP39 is actually a style implementation that lays out how copyright wallets produce the list of words (or "mnemonic codes") which make up a mnemonic https://bookmarkport.com/story22001114/ian-coleman-bip39-https-linktr-ee-bip39-not-known-details-about-bip39-list