Developer Simon Males has launched a browser-based Bitcoin puzzle game that offers 6 BTC to anyone whose graphics card finds the private key controlling one of Bitcoin’s longest-running public cryptographic challenges.
Krackpot targets Bitcoin Puzzle #71, an intentionally weakened wallet created as part of a 2015 challenge designed to demonstrate the difficulty of searching increasingly large private-key ranges. The address remains unsolved with approximately 7.1018 BTC, while Krackpot describes itself as the “world’s worst lottery” because of the extraordinary odds of finding the correct key.
Browser Uses Local GPU Power
Krackpot runs through WebGPU directly inside a compatible desktop browser without requiring users to install a dedicated application or create an account. Participants provide a Bitcoin payout address and allow their GPU to search the puzzle’s restricted keyspace locally.
Puzzle #71 limits the unknown private key to a range containing 2^70 possibilities, or roughly 1.18 sextillion candidates. That intentionally restricted range is fundamentally different from attempting to brute-force an ordinary Bitcoin private key drawn from the full secp256k1 keyspace.
Males built the project partly as a demonstration of that difference. His technical breakdown of the WebGPU implementation estimates that one gaming GPU would require roughly 830,000 years before expecting a successful hit. Even one million comparable GPUs searching continuously would bring the estimate down only to around one year.
Bitcoin’s resistance to future cryptographic attacks has received increased attention this year as researchers examine risks beyond conventional brute force. Strategy recently launched a $15 million Bitcoin security consortium that includes post-quantum cryptography among its early research priorities.
Winner Gets 6 BTC From Puzzle Wallet
If Krackpot finds the target key, the application is designed to construct a signed transaction locally and route it through a private submission channel rather than exposing the recovered key through a normal public broadcast.
Exactly 6 BTC would be sent to the participant’s chosen address, with the remaining balance directed to an address controlled by the developer. The project does not charge an entry fee or require participants to pool their computing resources.
The unusual challenge also arrives as real-world wallet weaknesses continue to demonstrate the difference between deliberately reduced cryptographic puzzles and accidental key-generation failures. Coinspect recently identified the Ill Bloom wallet flaw after roughly $5 million was drained, with weak randomness leaving thousands of addresses vulnerable.
Puzzle #71 Remains Unsolved
Bitcoin Puzzle #71 currently holds 7.10182686 BTC at address 1PWo3JeB9jrGwfHDNpdGK54CRas7fsVzXU, with the challenge still listed as unsolved.
Krackpot does not indicate that ordinary Bitcoin wallets can be cracked with consumer graphics cards. Its target exists specifically inside a dramatically reduced private-key range published for the puzzle, while properly generated Bitcoin keys remain outside the practical reach of conventional brute-force computing.
For Krackpot participants, the calculation remains deliberately unforgiving: approximately 2^70 possible keys, 6 BTC for the winner, and an estimated 830,000 years of searching for a single gaming GPU.
