What is a private key?
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A private key is a secret number — typically represented as a long hexadecimal string — that grants full control over a blockchain wallet. Every transaction you send is signed with this key, and that signature is what the network checks to confirm you authorized the action.
The key pair
Blockchain wallets rely on asymmetric cryptography, which produces two mathematically linked keys:
- Private key — kept secret. Signs transactions and proves ownership.
- Public key — derived from the private key. Used to generate your wallet address.
The derivation is one-way: anyone can compute the public key (and address) from the private key, but no one can reverse the process.
Private key vs. recovery phrase
| Concept | Scope | Purpose |
|---|---|---|
| Private key | Controls a single wallet | Signs transactions for that wallet |
| Recovery phrase (seed phrase) | Generates all private keys in a wallet hierarchy | Restores an entire wallet and its derived accounts |
A recovery phrase is a human-readable encoding of a master seed. From that seed, the wallet software deterministically derives each account's private key. Losing the recovery phrase means losing access to every account it generates.
Security
Anyone who obtains your private key can drain your wallet instantly and irreversibly. There is no "forgot password" flow, no support team that can reverse the transfer, and no on-chain mechanism to freeze stolen funds.
- Never share your private key or recovery phrase with anyone.
- Never enter either into a website, form, or message — legitimate services will never ask for them.
- Store backups offline, in a physically secure location.