Bip39 Mnemonic Code Converter Tool. Because of the cryptographic style of BIP-39, a weak passphrase would not lessen the security of the opposite wallets or help reveal the seed words. Anyone else who discovers the phrase can steal the bitcoins. It needs to be stored top secret, one example is https://bookmarkfriend.com/story18699635/bip39-https-linktr-ee-bip39-bip-39-no-further-a-mystery