Usually quoted as dollars per terahash per day, it folds together block reward, transaction fees, network difficulty and coin price. When hashprice falls below a machine's electricity cost per terahash, that machine is losing money.
It is the cleanest way to compare mining conditions across time, because it does not depend on any particular rig.
This definition is educational and not financial advice. Crypto is volatile and high-risk — always do your own research.
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