how metamask generate seed phrase

Metamask utilizes a cryptographically secure pseudorandom number generator (CSPRNG) to generate unpredictable entropy strings, which are then encoded into a 12-word seed phrase using the BIP39 word list and a checksum for added security.

Oct 31, 2024 at 09:31 pm

How Metamask Generates Seed Phrases

Metamask is a popular cryptocurrency wallet that allows users to store, send, and receive digital assets securely. One of the most important features of Metamask is its seed phrase, which is a 12-word mnemonic that gives users access to their wallet in case they lose their device or forget their password.

Here is a detailed guide on how Metamask generates seed phrases:

1. Entropy Generation

Metamask generates seed phrases using a cryptographically secure pseudorandom number generator (CSPRNG) that produces a series of random numbers. These random numbers are then hashed using the SHA-256 algorithm to create a unique and unpredictable string of characters.

2. Word List Selection

Metamask uses a predefined list of 2048 common English words known as the BIP39 word list. The BIP39 word list consists of words that are easy to remember and pronounce, making it easier for users to memorize and recover their seed phrases if needed.

3. Word Encoding

Once the entropy string has been generated, Metamask uses a mathematical formula to encode it into a sequence of numbers. These numbers are then used to select corresponding words from the BIP39 word list, forming the 12-word seed phrase.

4. Checksum Calculation

To ensure the integrity of the seed phrase, Metamask calculates a checksum from the first 11 words. The checksum is a single word that is appended to the end of the seed phrase. If the checksum does not match when the seed phrase is entered into Metamask, it will not be accepted.

5. Storage

The seed phrase is not stored on Metamask's servers. Instead, it is encrypted and stored locally on the user's device. This ensures that the seed phrase cannot be accessed by anyone other than the user who created it.

Importance of Seed Phrases

Seed phrases are crucial for recovering access to Metamask wallets. If a user loses their device or forgets their password, they can use their seed phrase to recreate their wallet and retrieve their assets. It is essential to keep the seed phrase safe and secure, as it provides access to all the funds in the wallet.

Users should never share their seed phrases with anyone, and they should consider storing them in a physical, offline location such as a safe deposit box or encrypted flash drive.