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Bitcoin proof-of-work tools
Four small tools for looking inside a Bitcoin block: decode a header, work out how long a search takes, read the genesis block byte by byte, and measure your own machine. They run entirely in your browser.
Block header calculator
Paste 80 bytes or fill in six fields. Get every field decoded, the double SHA-256 hash, the target from nBits, and a PASS or FAIL. 000000000019d6689c085ae165831e93… Open the calculator 02Leading zeros calculator
How long does it take to mine a hash with N leading zeros? Set a hash rate, from a laptop to the whole Bitcoin network, and see the average, the median and the odds. 16^12 hashes ÷ 137 GH/s Open the calculator 03Genesis block decoder
All 285 bytes of Bitcoin's block 0 in an interactive hex view, including the Times headline in the coinbase. Decode your own coinbase hex to text. 5468652054696d65732030332f4a616e… Open the decoder 04Browser vs ASIC
Mine a small block in your browser, measure your real hash rate, and see how long 8, 10, 11 and 12 zeros would take you next to a 137 GH/s mining chip. your browser · MH/s vs the chip · GH/s Start the raceWhy these exist
Strike a Block runs one real Bitcoin mining chip. You type a line, and the chip mines a standalone Bitcoin-format block carrying it, to 8, 10, 11 or 12 leading zeros. These tools are the working parts of that idea, taken out and put on the bench so you can check the claims yourself. Everything a plate says about itself can be re-verified with the header calculator.
Want the ideas from the beginning? The interactive lessons build up hashing, nonces and difficulty step by step.
Have a real chip strike your own line, from $6.99. One sentence of yours, mined into a standalone block by a Bitcoin ASIC. Not on Bitcoin's blockchain; the proof of work is real.