// GLOSSARY -- BLOCKCHAIN & CRYPTO FUNDAMENTALS

What is Public Key?

1 min read Updated

A public key is the cryptographic counterpart to a private key — freely shared to verify signatures and derive blockchain addresses, without revealing the private key that controls the account.

WHY IT MATTERS

Public key cryptography is blockchain's mathematical foundation. Your public key is derived from your private key through a one-way function (elliptic curve multiplication). It can be shared openly for signature verification.

In practice, users interact with addresses — hashed, checksummed derivatives of public keys — rather than raw public keys. When someone sends crypto, they send it to your address.

This asymmetric cryptography enables trustless verification: anyone can confirm a transaction was signed by a particular key without ever seeing the private key.

FREQUENTLY ASKED QUESTIONS

Is sharing my public key safe?
Yes — that's the point. Public keys are designed to be shared. Your address (derived from it) is visible on the blockchain for every transaction.
Public key vs address?
An address is derived from the public key through hashing. Addresses are shorter and include error detection. The public key is the underlying cryptographic value.
How does signature verification work?
When you sign with your private key, anyone with your public key can mathematically verify the signature — proving authorization without revealing the private key.

FURTHER READING

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