PUE Calculator
PUE: PUE = total facility energy ÷ IT equipment energy. Methodology stated, your own inputs only.
In short
PUE: PUE = total facility energy ÷ IT equipment energy. Methodology stated, your own inputs only.
Formula: PUE = total facility energy ÷ IT equipment energy.
What this calculator does
PUE: PUE = total facility energy ÷ IT equipment energy. Methodology stated, your own inputs only. Worked example, questions and limitations included.
Use it to turn Total facility energy in the period, IT equipment energy in the same period into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this data centers calculation.
Inputs and what they mean
- Total facility energy in the period
- — number value.
- IT equipment energy in the same period
- — number value.
How to use it
- Enter each value in the unit shown next to the box (use the unit converter first if your numbers are in other units).
- Check the breakdown to see every intermediate step.
- Read the limitations before relying on the result.
Formula
Methodology: Power Usage Effectiveness as defined by The Green Grid (also ISO/IEC 30134-2), using energy over a period rather than a single power reading.
State where IT energy is measured (UPS output, PDU or server).
Annual figures smooth out seasonal cooling.
PUE = total facility energy ÷ IT equipment energy.
Inputs used: Total facility energy in the period, IT equipment energy in the same period.
Worked example
A year
- 1,500,000 ÷ 1,000,000 = 1.500.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Says nothing about IT efficiency itself.
- Depends on measurement point.
- Results are estimates built only from the figures you enter. No electricity, fuel or gas price, equipment efficiency or benchmark is built in — tariffs vary by supplier, region and time, and equipment data must come from the manufacturer. Designs and installations must be checked by a qualified professional.
- The result depends on the values you enter for this pue calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Reference: The Green Grid
Last reviewed:
Common questions
Is there a target or industry average built in?
No. Results depend on climate, design, load and measurement point, so none is shown. Compare against your own history.
Power or energy?
The Green Grid recommends energy over a full year; an instant power ratio can mislead. Check the formula, example, and limitations on this page before using the result for a real data centers decision.
What is DCiE?
The reciprocal of PUE as a percentage — the share of energy reaching IT equipment. Check the formula, example, and limitations on this page before using the result for a real data centers decision.
How do I use the PUE Calculator?
Enter the required values for Total facility energy in the period, IT equipment energy in the same period. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the PUE Calculator use?
PUE = total facility energy ÷ IT equipment energy. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.
Can the PUE Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
Sources
Method based on The Green Grid.
Cite this page
Free Calculator. (2026, October 20). PUE Calculator. https://freecalculator.tech/tools/pue-calculator
"PUE Calculator." Free Calculator, 20 Oct. 2026, https://freecalculator.tech/tools/pue-calculator.
PUE Calculator — Free Calculator, https://freecalculator.tech/tools/pue-calculator
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