Bip39 Vs Electrum To create a seed phrase this fashion, You'll have a calculator that includes a RANDOM function (for making entropy). Find out more about making a seed phrase applying an offline calculator listed here. BIP39 specifies a list of 2048 words from which the mnemonic phrase is preferred. https://directoryhere.com/listings621203/bip39-last-word-checksum-not-known-facts-about-bip39-word-list