All terms
The secret number that controls your funds. Whoever has it owns the coins.
A private key is a very large random number. It mathematically proves ownership without ever being revealed, through digital signatures. Your wallet uses it to sign transactions, and the network verifies the signature against your public key.
There is no password reset. There is no support line. Anyone who obtains your private key can move everything instantly and irreversibly, and nobody can undo it.
A private key is 256 bits, which is roughly the number of atoms in the observable universe. Guessing one is not a realistic attack. Tricking you into revealing it is.
That a private key is a password you can change. There is no reset, no support desk and no way to rotate it while keeping the same address. If it is exposed, the only fix is moving everything to a new key before somebody else does.
Common questions
Can a private key be guessed or brute forced?
Is my seed phrase the same as my private key?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More foundations terms
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