3 Phase Power Calculator
Calculate three-phase real power, apparent power and reactive power from line voltage, current and power factor. Enter your own values to produce a transparent estimate.
Fill in the required fields to see your result.
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The primary output summarizes the selected scenario. Supporting outputs expose intermediate calculations so the result can be checked.
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How to Use This Calculator
Enter current values using the units shown. Review assumptions, compare scenarios and inspect the supporting outputs before interpreting the result.
Formula & Methodology
The calculator applies the formulas shown in the result logic to your inputs. It does not add hidden test data, engineering constants or manufacturer assumptions beyond the explicit formulas.
Worked example
A 400 V, 50 A three-phase load at 0.9 power factor uses about 31.2 kW of real power.
Planning estimate only. Actual outcomes may vary because of losses, tolerances, operating conditions, installation geometry, manufacturer specifications and real-world performance.
Educational planning tool only. Verify measurements, units, current standards and manufacturer information before making technical, financial or safety-critical decisions.
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Frequently Asked Questions
- What does the 3 Phase Power Calculator calculate?
- Calculate three-phase real power, apparent power and reactive power from line voltage, current and power factor.
- Is the result exact?
- No. It is an estimate based on the values, units and assumptions you enter. Real-world performance, tolerances, losses, conditions and manufacturer specifications can differ.
- Can I change the assumptions?
- Yes. Replace the example values with current figures for your vehicle, electrical system, pipe or mechanical application and compare multiple scenarios.
- Should I verify the result before using it?
- Yes. Check units, measurements, ratings and safety requirements. For safety-critical work, confirm the result with manufacturer data or a qualified professional.
Last updated 7/21/2026