Mining communities love complicated calculators with a dozen inputs, but the truth is that almost every electricity decision a home Malairte miner makes comes down to one short piece of arithmetic. Learn it once, carry it in your head, and you will never be at the mercy of an optimistic online calculator again.

The one formula

Energy used equals power times time. In the units that appear on your bill: kWh = watts × hours ÷ 1,000. From there, cost is simply kWh times your rate. That is the whole thing.

Plug in honest numbers and it works every time. A 350W rig for 24 hours: 350 × 24 ÷ 1,000 = 8.4 kWh. At an effective $0.16/kWh, that is $1.34 for the day. No mystery, no calculator, no spreadsheet.

The two numbers people get wrong

The formula is foolproof; the inputs are where people fool themselves.

  • Watts: use your measured wall draw, not the power supply's rating. The difference is often two or three times, which throws the whole estimate off.
  • Rate: use your all-in effective rate from dividing total bill by total kWh, not the supply price advertised in marketing. Delivery, taxes, and fees roughly double the headline number on many bills.

Scaling the answer

Once you have a 24-hour figure, every other scenario is just multiplication. Mine 12 hours instead of 24? Halve it. Mine only the nine off-peak hours? Scale by 9/24 and use the off-peak rate. Run two rigs? Double it. Because everything is linear, you can do most of these adjustments in your head while standing in front of the machine.

Turning cost into a decision

The math tells you cost; it does not tell you what MLRT is worth, and that is deliberate. To judge whether a day was net positive, take the MLRT your rig actually earned, value it at the current price, and compare to the cost the formula gave you. That comparison is a description of today, not a forecast - prices and difficulty move, and nothing here predicts where they go next.

Why memorising it matters

A miner who knows this formula cold makes better choices: they spot a wasteful idle baseline immediately, they understand exactly what an undervolt saves, and they are not swayed by hype calculators that quietly assume electricity is free. The discipline of always using real, measured inputs is what separates a grounded home mining setup from a vague hope. One formula, honest numbers, repeated forever.