Calculator
Block odds calculator for Bitcoin solo mining
The Block Odds calculator estimates the chance that a solo miner finds a Bitcoin block over practical time windows. It is built for small hobby setups like Bitaxe, NerdMiner, USB lottery miners, and mixed home-mining rigs.
What the calculator shows
Enter hashrate, network difficulty, block reward, BTC price, power draw, electricity cost, pool or service fee, and hardware cost. The calculator returns expected time to find a block, daily chance, monthly chance, yearly chance, expected BTC, yearly power cost, annual net expected value, profit per watt, and hardware payback.
Why block odds are different from profit calculators
A standard mining profitability calculator is usually built around pooled mining payouts. A block odds calculator is different: it answers the solo-mining question, which is whether your hashrate is likely to find a full Bitcoin block before the time horizon you care about.
Expected time is an average, not a countdown. A miner can get lucky early, or it can run forever without finding a block.
The plain formula
The rough probability per hash is one divided by difficulty times 2^32. More hashrate means more attempts per second. Higher network difficulty means each attempt is less likely to satisfy the current Bitcoin target.
Use it before buying more gear
Run your current miner first, then compare an upgrade. If the yearly odds barely move and the net expected value stays negative after power, the upgrade may still be fun or educational, but it should not be treated like an investment.