A public key is a cryptographic identifier that can be shared openly and is used to verify signatures or derive wallet addresses.

A simple way to think about it is a mailbox. Anyone can see the mailbox and send letters to it, but only the person with the private key can open the mailbox and take the letters out.

In crypto, public and private keys work as a pair:

• The private key is the secret that authorizes spending.
• The public key is used to prove that a signature came from the private key, without revealing the private key.

Most of the time, you do not directly use a public key. You use a wallet address, which is usually derived from a public key. Addresses are designed to be easier to share and safer to use in everyday transactions.

Understanding the difference matters because scammers sometimes misuse terminology. A wallet address or public key can be shared. A private key or seed phrase should never be shared.

Why this matters for your security

Public key cryptography is what makes it possible to prove ownership and approve transactions without exposing your secret key. When you understand what can be shared, you reduce the risk of giving away the one piece of data that can drain a wallet.

Ryder One keeps private keys in secure hardware, so you can sign transactions on-device without ever exposing secret key material to your phone or computer.

We make self-custody simple. Set up in 60 seconds for a lifetime of stress-free crypto security.

Get Ryder One

Related: What is a private key · What is a seed phrase · What is a hardware wallet