# What's a Private Key?

Access to your wallet is secured through the use of the combination of public and private keys.&#x20;

The public key can be thought of as being similar to your credit card or bank account number, while the private key is the secret PIN/CVC code used to validate access.&#x20;

Derivation from private to public is a one way function, meaning that although deriving a public key from a private key will always yield the same result, the reverse operation is nearly impossible.&#x20;

Currently, the standard private key is a 256 bit hexadecimal number, which means there are 16^64 possible combinations. That is, about 115,792 followed by 73 zeros, or more than three times the amount of stars in the universe.&#x20;