What Is a Private Key? A private key is a 256-bit number — in practice, a string of 64 hexadecimal characters — that cryptographically proves ownership of a specific blockchain address and authorises transactions from it. A raw private key looks like this: “ e9873d79c6d87dc0fb6a5778633389f4453213303da61f20bd67fc233aa33262 ` Every wallet address on Ethereum, Bitcoin, or any similar…