INVESTIGATIVE DOSSIER · RESEARCHED 03 OCT 2026
BITCOIN PUZZLE #73 · 73-BIT · OPEN

Bitcoin Puzzle #73

Still unsolved. The private key for this puzzle is an integer between 2^72 and 2^73 − 1, and whoever finds it can sweep 7.30013849 BTC from 12VVRNPi4SJqUTsp6FmqDqY5sGosDtysn4.

How to attempt Bitcoin puzzle #73

Only the address is known, so a solver has to walk the interval: multiply the secp256k1 generator by each candidate key, hash the compressed public key with SHA-256 and RIPEMD-160, and compare with the address’s hash160. On average that is 2^71 tests, about 2.36e+21. A single high-end GPU running BitCrack or keyhunt manages roughly a billion tests per second.

Try cracking #73 in your browser How solvers really attack it