The BIP39 (Bitcoin Improvement Proposal 39) mnemonic phrase is an important security element for crypto wallets using a deterministic wallet mechanism. It is a sequence of randomly selected words that provide a reliable means of restoring access to your wallet in the event of loss or damage. At you can find a list of words for Bip39 mnemonic phrases in English. 

Why do we need a mnemonic phrase?

The mnemonic phrase is designed to create a “root” of private keys, which in turn are used to generate wallet addresses and sign transactions. It simplifies the process of backing up and restoring a wallet since the user does not need to remember or store long strings of private keys. Instead, it is enough to remember just one mnemonic phrase.

Steps to create a BIP39 mnemonic phrase:

  1. Generating a random byte sequence: The first step is to generate a random byte sequence. This can be done using a cryptographically secure random number generator.
  2. Blocking: A sequence of bytes is divided into blocks of 11 bytes each. This is done to simplify the process, since each word of the mnemonic phrase will be represented by an index in a list of 2048 words.
  3. Checksum calculation: A checksum is added to a sequence of bytes to provide an additional level of security and integrity. The checksum is usually a portion of the last bits of the SHA-256 hash of the byte sequence hash.
  4. Conversion to mnemonic phrase: Every 11 bytes are converted to the corresponding word from the list of 2048 words that is defined in the BIP39 standard. This list contains words that are easy to remember and write.
  5. Creation of the final mnemonic phrase: The resulting words are combined into one line, forming a mnemonic phrase. This is the final phrase that can be used to restore the wallet.

The BIP39 mnemonic phrase plays a key role in ensuring the security and usability of crypto wallets. Its creation includes several steps, starting from generating a random sequence of bytes to forming a phrase from words that are easily remembered and perceived by the user. Correct creation and storage of a mnemonic phrase significantly affects the security of a crypto wallet and the safety of cryptocurrency assets.