Krackpot: crack Bitcoin Puzzle 71 for 6 BTC in your browser
The world's worst lottery. Someone still wins. Your GPU buys the tickets. No signup, no deposit, no pool.
New here? What this actually is
Back in 2015 someone locked some Bitcoin in a wallet and published the lock as a public puzzle for anyone to try. The key is one specific number out of a range so huge it is hard to picture. Krackpot puts your computer to work guessing numbers, fast, right in this browser tab. Guess the key and 6 BTC is yours. The odds are astronomical and we do not pretend otherwise, but the money is real and still unclaimed.
Your browser can't reach WebGPU
The search runs on your GPU through WebGPU, and this browser or device can't get to it right now. It's not you, and there's often a quick fix.
Chrome or Edge on a desktop give the smoothest run. Either way, you can still read how Krackpot works while you're here.
Where your 6 BTC lands if you win. No wallet? Any wallet app gives you one free.
PRIZE SPLIT NOTICE
On a hit, the signed transaction is built locally and automatically submitted through a private channel (never the public mempool): 6 BTC to your address, the remainder to bc1q5n4c8ey736k72e8jhd5uyuaquzte7ze0en04wj.
Free, and safe: it runs only in your browser and can't touch your files or wallet.
Enabled once the one-time capability check passes.
Checking capability of your processor…
Self-test of the WGSL math, hashing, and endianness on this GPU and driver. The search stays locked until every test passes.
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Grinding away? Add Krackpot to your home screen so it launches like an app and keeps working offline.
The odds, told honestly
keyspace ~1.18 sextillion keys · 2⁷⁰ · median of a random sweepTerrible odds. Real Bitcoin. Someone still has to win.
Good to know
What's Puzzle 71?
A wallet the Bitcoin Puzzle creator funded on purpose in 2015 as a public, solvable challenge. #71 is still uncracked. Verify it on-chain anytime.
Where does the money go?
If you find the key, the recovered private key stays in your browser. A signed transaction is built locally and submitted privately with the split above: exactly 6 BTC to the payout address you enter, and the remainder to the developer. It is never sent to the public mempool, because a revealed puzzle key can be front-run and stolen there. The signed hex is always shown, whether or not the automatic submission goes through, so you can submit it yourself, privately.
What happens to the found key?
The recovered key never leaves your browser, and signing happens locally with nothing sent to a server. A revealed puzzle key is a race, so the claim transaction is submitted immediately and through a private channel, never a public explorer, to keep it from being front-run. The key and signed hex are shown too, so you have them on record.
What are the real odds?
Astronomical, and we say so plainly. A fast gaming GPU checks tens of millions of keys a second and would still need close to a million years to expect a hit. Even every Steam gamer searching at once would take about a week. Someone still has to win.
How does this compare to real solving tools?
Krackpot is the easy way in, not the fast way. Dedicated GPU solvers run thousands of times faster, but they need a real rig, CUDA drivers, and the command line. Krackpot's trade is different: no install, no signup, just a browser tab and a crowd of free tickets that grows every time someone shares their link. Slower per machine, zero effort to join. None of them beats the math anyway.
Do I need to keep the tab open?
Yes. Browsers throttle or pause GPU work in backgrounded tabs, so the search only runs while this tab is visible.
How does it actually work?
Every key is turned into a Bitcoin address entirely on your GPU: secp256k1, SHA-256, and RIPEMD-160 all run as WebGPU compute shaders, with nothing sent to a server. The full write-up covers the WGSL math, the GPU watchdog calibration, and the mobile findings: how Krackpot works.