Get the extension What is a private key in crypto?
A private key is a secret number that controls one address on one blockchain. It produces the signatures that authorise transactions. From it anyone can compute the public key and the address, but not the other way round.
Why it matters
Signing requires the private key, so any software that signs for you has to hold it somewhere. Where decides your security: in a browser, it is one compromise away from theft; on an offline device, an attacker would first have to take the device and learn your master password.
How Locker Protocol Wallet handles it
Locker Vault derives your private keys from your recovery phrase and keeps them encrypted with your master password, on a device that stays offline. The extension only ever sees public keys and addresses, and revealing a key on the Vault asks for the password every time.
Questions
Is a private key the same as a seed phrase?
No. The seed phrase generates many private keys, one per address and chain. Losing one private key exposes one address; losing the phrase exposes all of them.
Can someone guess my private key?
Not by chance: the number of possible keys is far beyond anything a computer can search. Keys are stolen, not guessed, which is why where they are stored matters.