Public Key, Private Key and Address: What Is the Difference

When you use a crypto wallet, three concepts appear repeatedly: private key, public key, and address. They are related but distinct, and confusing them leads to mistakes — including irreversible ones.

A private key is a randomly generated number, typically 256 bits long. It is the root of your ownership. Whoever holds the private key controls the funds associated with it. There is no recovery mechanism: if you lose the private key and have no backup, the funds are inaccessible permanently.

The private key must never be shared. It is used to sign transactions, proving that you authorised a transfer without revealing the key itself.

The public key is derived from the private key using elliptic curve cryptography. The derivation is one-way: you can compute the public key from the private key, but not the reverse.

The public key is used to verify signatures. When you sign a transaction with your private key, anyone can verify the signature using your public key — confirming that the transaction was authorised by the private key holder — without learning the private key.

An address is derived from the public key, typically by hashing it and encoding the result. On the XRP Ledger, an address looks like rHb9CJAWyB4rj91VRWn96DkukG4bwdtyTh. On Bitcoin, it might start with 1, 3, or bc1.

The address is what you share when you want to receive funds. It is safe to make public — knowing your address does not allow anyone to spend your funds.

Private key → (elliptic curve multiplication) → Public key → (hash + encoding) → Address

Each step is one-way. You can move forward through the chain but not backward.

Sharing your address is safe. Sharing your public key is generally safe (though some advanced protocols use it directly). Sharing your private key — or your seed phrase, which generates it — gives complete control of your funds to whoever receives it.

This article is for information only.