Crypto Glossary

Private Key

A secret string of characters that proves you own a crypto address. Anyone who sees it can spend your funds.

Definition

A private key is a long secret number, usually shown as a string of letters and digits. It is what your wallet uses to sign transactions and prove that funds belong to you.

If someone else gets your private key, they can move your crypto and you cannot reverse it. Wallets usually hide the raw key behind a password or a seed phrase so you do not have to handle it directly.

Related terms

Source: What The Block! Dictionary v1.0 (last updated 2026-04-25).

See the full What The Block! catalogue

What The Block! covers more than 2,000 plain-English crypto terms, delivered as embeddable hover-state tooltips for trading interfaces.