Mine Bitcoin<number>
Your browser hashes Bitcoin<number>, counting upward from a random starting point and keeping whichever result is lowest. Real SHA256d, real brute force, and the best hash you find can go on the leaderboard.
Random for every visitor, so you are not re-checking numbers someone else already tried.
Mining this faster
A browser tab manages a few hundred thousand hashes per second. The same search compiled for a GPU does several billion, which is roughly the difference between a hash with 30 leading zero bits and one with 45. If you want to compete for the top of the leaderboard, that is what it takes.
bitcoin_miner.cu is one file of CUDA that hashes the same string and scores it the same way, with no dependencies beyond the CUDA runtime. It runs on any GPU from roughly 2014 onward, and a rented one costs a fraction of a dollar per hour.
curl -fsSLO https://bestbitcoinhash.com/gpu/bitcoin_miner.cu
nvcc -O3 -arch=native bitcoin_miner.cu -o bitcoin_miner
./bitcoin_miner --message Bitcoin --start 4068315053529029805 --duration 3600Pick your own --start. It defaults to zero, and two people who both leave it there hash exactly the same strings. It checks itself against an independent CPU implementation before it starts, prints every new best as it finds one, and writes the answer to gpu_best.txt. Submit it the same way as anything mined here. Full instructions.
What this is not
This page runs the same hash function Bitcoin mining runs, against the same kind of odds, which makes it a decent way to feel how the search behaves. It is not Bitcoin mining.
The starting number is drawn at random for every visitor out of a space of 1021, so two people almost never grind the same stretch of numbers. Nothing is lost by starting high: the hashes are just as unpredictable at 1020 as at zero, and the low numbers have been picked over already.
What gets hashed here is the ASCII string Bitcoin<number>, not an 80-byte block header. Nothing is connected to the Bitcoin network, no block is being competed for, and nothing can be earned. A browser manages a few hundred thousand hashes per second where an ASIC does hundreds of trillions, so the gap is around nine orders of magnitude.