Seed phrase

A seed phrase is a list of ordinary words—commonly 12 or 24—that encodes the master secret from which a wallet derives all its private keys and addresses. Written down in order, it can restore an entire wallet on a new device. Because it unlocks everything, anyone who obtains it can take the funds, so it should be kept offline and never typed into websites.

A common misconception is that a seed phrase is just a password you can reset; it cannot be changed or recovered by any provider. See seed phrases explained for detail.