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What is a private key

A private key is a secret cryptographic key used to control cryptocurrency funds and sign blockchain transactions.

Private keys are the core security mechanism of cryptocurrency systems. Anyone who gains access to a private key can control the associated crypto assets.

How a private key works​

Most cryptocurrencies use a system based on two keys:

  • a public key
  • a private key

The public key is used to receive funds, while the private key is used to sign transactions and prove ownership.

Technically, the public key is derived from the private key. However, it is computationally infeasible to determine the private key from the public key.

Where private keys are stored​

Private keys are typically stored in:

  • desktop or mobile wallet applications
  • hardware wallets
  • specialized secure applications
  • hardware security modules (HSM)

For additional security, keys are often protected with a seed phrase.

Why protecting the private key is important​

If a private key is lost or stolen, the associated cryptocurrency may be permanently lost.

To reduce risks, users should:

  • store keys offline when possible
  • use hardware wallets
  • never share private keys with others

FAQ​

Can a private key be recovered?​

Usually not. However, access to a wallet can sometimes be restored using a seed phrase.

What happens if a private key is lost?​

Access to the cryptocurrency stored in that wallet may be permanently lost.

Should you share your private key?​

No. A private key must always remain confidential.