Seed Phrase (Mnemonic)

Seed phrase (also called a recovery phrase or mnemonic) is a sequence of 12 or 24 words that represents the master key to a cryptocurrency wallet. Anyone with the seed phrase has full control over the wallet — it can restore all addresses and funds on any compatible software or hardware wallet.

BIP-39 standard

Most modern wallets follow BIP-39 (Bitcoin Improvement Proposal 39), proposed in 2013. BIP-39 defines:

• A wordlist of 2,048 English words, each distinct enough to avoid confusion
• Derivation of a seed phrase from random entropy:
  • 12 words = 128 bits of entropy
  • 24 words = 256 bits of entropy
• A checksum built into the last word so invalid phrases are rejected

How it's used

The seed phrase is converted into a cryptographic seed, from which all private keys in the wallet are deterministically derived (BIP-32 / HD wallets). This is why a single phrase can restore thousands of addresses across multiple cryptocurrencies.

Storing your seed phrase

• Write it down on paper or metal — never store digitally on a phone, cloud, or email
• Keep multiple copies in geographically separated locations
• Never share it — no legitimate support team will ever ask for your seed phrase
• Never type it into a website unless you're restoring a wallet on a trusted app
• Consider metal backups (engraved or stamped) to survive fire and water damage

If your seed phrase is exposed, move funds to a new wallet immediately.

See also

• Private key
• Public key
• Phishing