Power Factor Correction Estimator
Estimate the reactive-power change implied by a target power factor. Enter positive power factors between zero and one and choose a target higher than the measured value.
How to use this calculator
- Enter the real power (kw) using the units shown beside the field.
- Enter the current power factor using the units shown beside the field.
- Enter the target power factor using the units shown beside the field.
- Review the calculated values and check that the assumptions match your scenario.
- Change one input at a time when comparing scenarios so you can see which assumption drives the result.
Formula and assumptions
Required compensation kVAr = kW × [tan(arccos(current PF)) − tan(arccos(target PF))] when target PF exceeds current PF.
- This is an initial estimate only. Actual correction equipment needs measurements, harmonics analysis, load variation checks, switching design and qualified electrical review.
- The result is computed from the values you provide; it does not fetch external rates, live account data or local rules.
Worked examples
Worked example
For 75 kW moving from 0.72 to 0.95 power factor, the simplified required compensation is roughly 44 kVAr.
Example inputs: Real power (kW) = 75, Current power factor = 0.72, Target power factor = 0.95.
Compare the displayed output with your own measurements before using it in a decision.
Understanding the result
This is an initial estimate only. Actual correction equipment needs measurements, harmonics analysis, load variation checks, switching design and qualified electrical review.
Results are estimates based on the stated model. If the situation depends on measured conditions or contractual specifications, use those source values rather than typical assumptions.
Important notes
This is an initial estimate only. Actual correction equipment needs measurements, harmonics analysis, load variation checks, switching design and qualified electrical review.
Frequently asked questions
What formula does this calculator use?
It uses the method described above: Required compensation kVAr = kW × [tan(arccos(current PF)) − tan(arccos(target PF))] when target PF exceeds current PF.
What should I verify before relying on the result?
This is an initial estimate only. Actual correction equipment needs measurements, harmonics analysis, load variation checks, switching design and qualified electrical review.
Can I compare different scenarios?
Yes. Change the inputs while keeping units and definitions consistent, and record the assumptions used for each scenario.
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.