A seed phrase (also called a recovery phrase) is a sequence of usually 12 or 24 English words from which every private key in a wallet can be restored.
When a new wallet is set up, the software generates a random word sequence following a standardized procedure (BIP-39). Mathematically, an unlimited number of private keys – and therefore addresses – can be derived from this seed phrase.
If the device holding the wallet is lost or damaged, the seed phrase alone is enough to restore every balance on a new device. That is exactly what makes it both the most valuable and the most vulnerable part of a crypto wallet.
Experts recommend storing the seed phrase only offline and on physical media (e.g. paper or engraved metal) in a secure location – never as a photo, in a notes app, or in the cloud.
