Seed Phrase
A seed phrase (also called a recovery phrase or mnemonic) is a human-readable sequence of 12 or 24 words that encodes the master secret from which all private keys in a wallet are derived. It is the ultimate backup for your bitcoin.
How It Works
A seed phrase converts a large random number (128 or 256 bits of entropy) into a sequence of words drawn from a standardized list of 2,048 English words defined by BIP39. The 12-word format encodes 128 bits of entropy, while 24 words encode 256 bits. The final word includes a checksum to catch transcription errors. From this seed, a master key is derived, and from that master key, billions of individual private keys can be generated deterministically.
This means your entire wallet — every address, every key, past and future — is encoded in those words. If your hardware wallet is destroyed, lost, or stolen, you can recover everything by entering your seed phrase into a compatible wallet. This is both the greatest convenience and the greatest risk of the system.
Proper seed phrase storage is non-negotiable for self-custody. Write it down on paper immediately, then transfer it to a metal backup for durability. Never store it digitally — not in a photo, not in a notes app, not in cloud storage, not in email. Consider geographic distribution of backups and use a passphrase for additional protection.
Key Points
- 12 or 24 words encoding the master secret for your entire wallet
- Standardized by BIP39 using a 2,048-word dictionary with built-in checksum
- Enables complete wallet recovery on any compatible device
- Must be stored offline, physically secure, and never digitized
- Metal backups protect against fire, flood, and physical degradation