Bip39 Seed Phrase. Is passphrase similar to PIN? No, a passphrase is just not the same as a PIN. A passphrase, inside the context of Bitcoin wallets, is an extra layer of security to the wallet that actually works together with your seed phrase to encrypt and safeguard your wallet. https://mixbookmark.com/story4195421/bip39-passphrase-https-linktr-ee-bip39-getting-my-bip39-wallets-to-work