Hong Life CalculatorsUnderstanding the cryptocurrency footprint calculator — concept and principle
How much electricity and carbon dioxide does a Bitcoin transaction represent? This calculator divides the Bitcoin network's yearly electricity use and emissions evenly among its on-chain transactions, then multiplies by the number of transactions you enter. It also shows the network's annual emissions and average power. The per-transaction figure is an allocation, not the effect of one extra transaction.
How it is calculated
Electricity per transaction (kWh) = network TWh × 10⁹ ÷ (transactions per day × 365)
CO₂e per transaction (kg) = kWh × emission intensity (g/kWh) ÷ 1,000
Your share = per-transaction values × your transactions
Network emissions (Mt) = TWh × g/kWh ÷ 1,000
Average power (GW) = TWh × 1,000 ÷ 8,760 h
- Defaults: 138 TWh per year and about 288 g CO₂e per kWh, from the Cambridge Centre for Alternative Finance 2025 report; about 660,000 transactions per day.
The principle
Bitcoin miners compete to add blocks by performing huge numbers of hash computations, and the network's electricity use follows the total hash rate. That rate depends mainly on the block reward and the bitcoin price, not on the number of transactions. So dividing energy by transactions is a way of sharing out responsibility, like dividing a bus's fuel among its passengers, rather than a measure of what one transaction causes. Payments on second layers like the Lightning Network, or batched by exchanges, are not counted as separate on-chain transactions.
Worked example
Default inputs: 10 transactions, 138 TWh per year, 288 g CO₂e/kWh, 660,000 transactions per day.
- Transactions per year = 660,000 × 365 = 240.9 million.
- Electricity per transaction = 138 × 10⁹ ÷ 240.9 × 10⁶ = 573 kWh.
- CO₂e per transaction = 573 × 288 ÷ 1,000 = 165 kg.
- Your share for 10 transactions = 5,729 kWh and 1,650 kg CO₂e.
- Network emissions = 138 × 288 ÷ 1,000 = 39.7 Mt; average power = 138,000 ÷ 8,760 = 15.75 GW.
| Network transactions per day | Electricity per transaction (kWh) |
|---|---|
| 165,000 | 2,291 |
| 330,000 | 1,146 |
| 495,000 | 764 |
| 660,000 | 573 |
| 825,000 | 458 |
| 990,000 | 382 |
| 1.32e+06 | 286 |
How to read the result
The Cambridge report estimated Bitcoin's electricity at about 0.5% of world electricity, with just over half from sustainable sources. Per-transaction figures are much larger than for card payments, but the comparison is contested because of the allocation issue described above. Network energy changes month by month with the hash rate, so update the inputs with current estimates.
Common mistakes
- Interpreting the result as the extra energy caused by your transaction.
- Using outdated network energy or transaction numbers.
Frequently asked questions
Does one transaction really use 573 kWh?
That is an average share of network energy; one extra transaction adds almost nothing at the margin.
Why does Bitcoin use so much electricity?
Proof-of-work mining requires vast numbers of hash computations to secure the network.
Do other cryptocurrencies use as much?
Proof-of-stake networks use far less energy, so these figures do not apply to them.
Sources: Cambridge Centre for Alternative Finance, "Cambridge Digital Mining Industry Report: Global Operations, Sentiment, and Energy Use" (April 2025)