Public Key
A public key is a shareable cryptographic code used to receive funds or verify digital signatures without revealing the matching private key.
A public key is one half of a cryptographic key pair, the other half being a private key. It is designed to be shared openly, while the private key must remain secret. In cryptocurrencies, a public key helps prove ownership and enable secure transactions. It is mathematically linked to the private key, but it should be practically impossible to work backward from the public key to discover the private key.
Public keys are used to verify digital signatures: if someone signs a transaction with their private key, the network can use the related public key to confirm that the signature is valid. A wallet address is often derived from a public key, making it a shorter or more convenient identifier for receiving crypto. A simple comparison is an email address and password: you can share your email address so others can contact you, but only the password lets you control the account. Similarly, a public key can be shared, but the private key controls access.
Other terms in Cryptography & Privacy
CoinJoin
A privacy technique that combines multiple users’ cryptocurrency payments into one transaction to make input-output links harder to trace.
Crypto Mixer
A service or protocol that blends cryptocurrency from many users to make transaction trails harder to trace on a public blockchain.
Digital Signature
A digital signature is cryptographic proof that a message or transaction was approved by the holder of a specific private key.
Fully Homomorphic Encryption
A cryptographic method that lets data be processed while still encrypted, so only the key holder can reveal the final result.