Digital assets
Private key
Also called Seed phrase or Self-custody
The secret that proves ownership of a crypto holding, and the only thing that does.
How it works
Whoever holds the key controls the asset. There is no institution able to reverse a transaction, restore access, or verify identity.
Self-custody removes counterparty risk and replaces it with the risk of your own error — a lost key is permanent, and there is no recovery process.
Where it misleads people
Holding crypto on an exchange means the exchange holds the key. Several large exchanges have failed with customer assets, which is the origin of the phrase "not your keys, not your coins".
Related terms
More in Digital assets
Educational reference only. Nothing here is investment advice or a recommendation to buy or sell anything, and tax treatment depends on your own circumstances and the country you are in.