Formula & Calculator

kVA to kW Conversion

Converts apparent power in kVA to real power in kW using the power factor.

Energy & BillingPower Conversion

kVA to kW Conversion Calculator kW = kVA × cos θ

kW = kVA × cos θ
kW = real power  ·  kVA = apparent power  ·  cos θ = power factor (0 to 1)
⟹ Solve kW, kVA, cos θ
kW
kVA
Please fix the errors above.
Solve for:
Presets:
Real Power
kW: kVA: PF:
✓ Copied!
Power Factor Gauge
Low (< 0.70) Medium (0.70 – 0.90) High (> 0.90)
kW = kVA × cos θ  ·  Power factor (cos θ) ranges from 0 to 1. Real power kW = useful power.
kW = kVA × cos θ
kVA to kW Conversion

Variables

SymbolQuantityUnit
kWReal powerkW
kVAApparent powerkVA
cos θPower factordimensionless

What it means

The conversion from apparent power (kVA) to real power (kW) is given by kW = kVA × cosθ, where cosθ is the power factor. This conversion is essential for sizing electrical equipment and for understanding the actual power consumed. For a purely resistive load, cosθ=1, so kW = kVA. For inductive loads (motors, transformers), the power factor is less than 1. Example: A 10 kVA generator with a load having a power factor of 0.8 can deliver 10 × 0.8 = 8 kW of real power. The remaining 2 kVA is reactive power. This relationship is used to determine the required kVA rating for a given kW load.

Worked example

kVA to kW – Practical Example

Real‑World
Scenario: A generator is rated at 10 kVA with a power factor of 0.8. How much real power (kW) can it deliver?
ParameterValue
kVA10
cos θ0.8
FormulakW = kVA × cos θ
1kW = 10 × 0.8 = 8 kW
Final Design kW = 8 kW ✓ Real power
Why: Real power = apparent power × power factor – important for sizing equipment.

Common mistakes

Watch for unit mismatches (W vs kW, single- vs three-phase) and remember to include power factor or efficiency where the formula requires it.

Applications

kVA to kW conversion kW = kVA × cosθ converts apparent power to real power. This is used to calculate the actual useful power from a transformer or generator rating. Engineers use it to size equipment, to manage power factor, and to avoid overloading. This conversion is common in power system design.

  • Transformer and generator sizing for real power
  • Power factor and load management
  • Electrical installation design and capacity planning
  • Energy efficiency analysis
  • Educational understanding of power factor