Power Factor Correction Calculator
Fill in the values and the answer updates as you type.
How the Power Factor Correction Calculator works
Capacitor kVAR = kW × (tan φ₁ − tan φ₂), where φ = arccos(power factor). Raising power factor lowers current and apparent power for the same real load, which can cut utility penalties and cable losses. Power factors must be between 0 and 1. Example: with the default values, capacitor size needed comes to 55.3 kVAR.
Inputs and results
The Power Factor Correction Calculator takes 3 inputs and gives 4 results.
What you enter
- Real power load (kW) — starts at 100.
- Existing power factor — starts at 0.75.
- Target power factor — starts at 0.95.
What you get
- Capacitor size needed (kVAR)
- Apparent power before (kVA)
- Apparent power after (kVA)
- Current reduction
Example: Power Factor Correction Calculator with the starting values
With real power load 100 kW, existing power factor 0.75 and target power factor 0.95, the calculator returns:
| Capacitor size needed (kVAR) | 55.3 |
|---|---|
| Apparent power before (kVA) | 133.3 |
| Apparent power after (kVA) | 105.3 |
| Current reduction | 21.05% |
Change any value above and the results update straight away.
Power Factor Correction Calculator FAQ
How do I use the Power Factor Correction Calculator?
Enter real power load, existing power factor and target power factor in the fields, then read capacitor size needed (kvar), apparent power before (kva), apparent power after (kva) and current reduction in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Power Factor Correction Calculator calculate?
Capacitor size needed to improve power factor. It returns capacitor size needed (kvar), apparent power before (kva), apparent power after (kva) and current reduction from the 3 values you provide.
What values does the Power Factor Correction Calculator start with?
It opens with real power load 100 kW, existing power factor 0.75 and target power factor 0.95 so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Power Factor Correction Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Power Factor Correction Calculator for important decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.