Bip39 Seed Phrase. Is passphrase similar to PIN? No, a passphrase is not similar to a PIN. A passphrase, during the context of Bitcoin wallets, is an extra layer of security in your wallet that works along with your seed phrase to encrypt and guard your wallet. A PIN, on https://bookmarknap.com/story10047496/bip39-mnemonic-https-linktr-ee-bip39-bip39-words-an-overview