Bitcoin Per Watt Calculator
Compare mining hardware on the metric that matters. Pick an ASIC preset (or enter custom hashrate and power), add your electricity price and the network payout per terahash, and this bitcoin per watt calculator computes BTC per watt per day, the J/TH efficiency rating, and your estimated daily profit after power costs. It is a static estimator, not a live profitability feed: you bring the payout figure from your pool or a profitability site, and the tool does the arithmetic honestly, with every step shown.
Estimate only. BTC per TH/s per day moves with network difficulty and hashprice; pool fees, firmware fees, downtime, hardware cost and difficulty changes are not included. If you leave the BTC price blank, the tool reports power cost instead of profit.
Quick Answer
An Antminer S21 Pro (234 TH/s at 3,510 W) earning 0.000000452 BTC per TH/s per day produces 3.013e-8 BTC per watt per day at 15.0 J/TH. At $77,975 BTC and $0.06/kWh, that is $8.25/day revenue minus $5.05/day power: $3.19/day profit. The same machine breaks even near $0.098/kWh on these inputs, so a power price only a few cents higher wipes the margin out entirely.
Worked example, checked against this exact tool
Every number in this section is the tool's own output for the pre-filled inputs, not a rounded estimate from elsewhere. The lead-in matters because mining articles routinely quote figures from a different day's difficulty or price, and those figures cannot be reproduced. Here, they can: change nothing, press Calculate, and you get the same chain.
Antminer S21 Pro: 234 TH/s at 3,510 W, BTC per TH/s per day 0.000000452, electricity $0.06/kWh, BTC $77,975. BTC per day = 234 times 0.000000452 = 0.00010577. BTC per watt per day = 0.00010577 divided by 3,510 = 3.013e-8. Efficiency = 3,510 divided by 234 = 15.0 J/TH. Revenue $8.25/day, power cost $5.05/day (84.24 kWh), profit $3.19/day. Monthly profit on the same basis is $95.79, which is the tool's daily profit times 30, and it is an operating margin only: it excludes the machine's purchase price, pool fees, downtime and difficulty changes.
J/TH: the number that decides a miner's lifespan
Hashrate gets the headlines, but joules per terahash decides which machines stay profitable when difficulty rises or price falls: J/TH = watts divided by TH/s. A 23 J/TH machine (S19k Pro) spends roughly twice as much on power per unit of work as an 11 J/TH machine, so when the margin compresses, the efficient machines keep hashing and the inefficient ones get unplugged. That is why experienced miners shop efficiency first and hashrate second. The presets built into this tool span the current air-cooled range, and their ratings are simple division, which you can check in the table below.
| Preset machine | Hashrate | Power | J/TH |
|---|---|---|---|
| Bitdeer SEALMINER A4 Pro Air | 336 TH/s | 3,662 W | 10.9 |
| Antminer S23 Air | 318 TH/s | 3,498 W | 11.0 |
| Bitdeer SEALMINER A3 Pro Air | 290 TH/s | 3,625 W | 12.5 |
| Avalon A16XP | 300 TH/s | 3,850 W | 12.8 |
| Antminer S21 XP Air | 270 TH/s | 3,645 W | 13.5 |
| Antminer S21 Pro | 234 TH/s | 3,510 W | 15.0 |
| Antminer S21 | 200 TH/s | 3,520 W | 17.6 |
| Antminer S19k Pro | 110 TH/s | 2,530 W | 23.0 |
Two cautions belong with the table. First, a lower J/TH is better, but it is not the whole purchase decision: a very efficient machine can still be a bad buy if its price per terahash is high, since this tool's profit figure excludes hardware cost. Second, manufacturer ratings are measured under controlled conditions; real wall draw moves with ambient temperature, firmware and overclocking, so treat the preset as a starting point and overwrite it with your own metered draw when you have it. For the energy side of the bill in general, our cost of energy calculator prices any device's consumption the same way, watts times hours times price.
The profit chain, step by step
Five numbers link together into one verdict. Here is the chain in the order the tool computes it, so you can audit any result by hand.
BTC per day = hashrate (TH/s) times BTC per TH/s per day (from your pool or a profitability site). BTC per watt per day = BTC per day divided by power (W): the per-watt efficiency of earnings, and the headline metric of this page. Revenue per day = BTC per day times BTC price. Power cost per day = watts times 24 divided by 1000 times $/kWh. Profit per day = revenue minus power cost. The full project return also needs hardware cost, downtime, pool fees and difficulty changes, but the operating margin above is the number that decides whether a machine stays plugged in. If you want the same revenue-minus-cost logic applied to a business rather than a miner, our profitability calculator runs it in general form.
What BTC per watt tells you
It answers the question "how much coin does each watt earn?" Two machines can have the same daily revenue while one burns far more power to get it; BTC per watt per day exposes that gap in a single number, which is exactly what you need when power, not hardware, is your scarce resource.
What J/TH tells you
It answers the question "how much energy does each unit of work cost?" J/TH is independent of price, difficulty and payout, so it survives every market move. A machine's J/TH never improves with age, while its revenue per watt falls as difficulty rises, which is why J/TH is the better long-life comparison.
Electricity price decides everything
The same S21 Pro at different power prices, holding every other input at the worked example, shows how fast the verdict flips. The table below is the tool's own output at each price, not a separate model.
| Electricity price | Power cost per day | Revenue per day | Profit per day |
|---|---|---|---|
| $0.05/kWh | $4.21 | $8.25 | $4.04 |
| $0.06/kWh | $5.05 | $8.25 | $3.19 |
| $0.09/kWh | $7.58 | $8.25 | $0.67 |
| $0.12/kWh | $10.11 | $8.25 | -$1.86 |
At 9 cents the machine is barely above water, and at 12 cents it loses money before pool fees. The breakeven price on these inputs is about $0.098/kWh: revenue of $8.25 divided by 84.24 kWh per day. That is why mining concentrates where power is cheap, and why a cheap inefficient miner can cost many times its purchase price in electricity over its life. Before buying, run your real tariff, not a headline rate: delivery charges, demand charges and taxes can push an advertised 6-cent rate well past breakeven. And if the coin price you use is a premium over spot rather than spot itself, our bitcoin premium calculator measures that gap before you feed a price into this tool.
What competing calculators miss
Profitability sites such as CoinWarz and WhatToMine need live network data and answer a different question: what is profitable right now, on today's difficulty and price. Formula articles give the equations but no tool. This page is the static middle ground: presets for current hardware, the J/TH rating miners actually compare, BTC per watt per day, and the full revenue-cost-profit chain from inputs you can look up in a minute. Three specific gaps in rivals shaped this tool. First, many calculators report profit per day but not profit per watt, so an efficient and an inefficient machine look alike when their revenue matches. Second, few show the breakeven power price, which is the single number that tells a buyer whether their tariff works at all. Third, live tools hide their payout assumption inside a difficulty feed, so their answer cannot be reproduced tomorrow; here the BTC per TH/s per day input is visible, editable and shown in the formula line under every result. One honest limit remains: daily profit here is not a return on investment. To judge what reinvested profit grows into over time, our saving growth calculator models compounding growth on a balance, which is a different calculation from this page's daily operating margin.
Frequently Asked Questions
Bitcoin per watt per day = (hashrate times BTC per TH/s per day) divided by power in watts. The S21 Pro example gives 3.013e-8 BTC per watt per day.
Joules per terahash: watts divided by TH/s. Lower is better; it measures energy per unit of mining work, and it does not depend on price or difficulty.
The presets in this tool run from 10.9 to 23.0 J/TH, with the current air-cooled machines clustered at 10.9 to 13.5 J/TH. Older machines at 20 J/TH or above struggle unless power is very cheap.
Revenue (BTC per day times price) minus power cost (watts times 24 divided by 1000 times $/kWh). Pool fees, typically 0 to 2 percent according to CoinWarz, come off revenue on top of that in a full model.
Profitability sites publish it, and pools report it for their own payouts. It moves with difficulty and hashprice, so refresh it before trusting any profit figure.
Usually for the worse: power rises faster than hashrate, so efficiency degrades even as output grows. If you overclock, measure wall draw and enter it as a custom machine rather than trusting the preset.
Difficulty rose or price fell while its J/TH stayed fixed, so the power cost per coin now exceeds the revenue per coin. No setting change fixes a J/TH gap that large; only cheaper power or a more efficient machine does.
3,510 W times 24 hours = 84.24 kWh per day, which is $5.05 at $0.06/kWh. The tool shows the same kWh figure in its power cost line for any machine.
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References
- CoinLaw. How to Calculate Crypto Mining Profitability in 2026: Easy Formula Accessed October 25, 2026.
- BitcoinVersus. Top 5 Most Efficient Air-Cooled Bitcoin Miners in 2026 Accessed October 25, 2026.
- Odaily. Bitcoin Mining Profitability Calculator: Real-Time Estimates of Hashrate Revenue, Electricity Costs, and Shutdown Price Accessed October 25, 2026.
- Altcoin Investor. Is Bitcoin Mining Still Profitable? 2026 Economics Analysis Accessed October 25, 2026.
- MillionMiner. Best Bitcoin Miners 2026: Every ASIC Ranked by Profit Accessed October 25, 2026.
- D-Central. Is Bitcoin Mining Profitable in 2026? Accessed October 25, 2026.
- CoinWarz. Bitcoin Mining Calculator Accessed October 25, 2026.
- D-Central. Exploring ASIC Efficiency: Breaking New Ground in Bitcoin Mining Accessed October 25, 2026.