Amps to Watts Calculator

Amps and watts are two sides of the same current: one measures flow, the other measures the work the flow carries. To move between them you need the voltage and, for anything with a motor or ballast, the power factor.

Amps to Watts Calculator converts current to real power for single-phase and three-phase systems — watts, kW and kVA shown together with the formula updating as you change any value.

It is the everyday conversion for wiring checks, equipment selection and supplier questions. Everything runs in the browser; nothing is uploaded.

• Single and three-phase: Choose the system and the formula adjusts.
• Power factor input: 1 for resistive, 0.7-0.9 for motor loads.
• Full output: Watts, kilowatts and apparent kVA on every run.
• Live formula line: The calculation shown exactly as computed.
• Export: Copy or download the conversion as text, CSV or JSON.
• Learning guide: When amps x volts is not enough.

1. Enter the current in amps.
2. Enter the voltage — line-to-neutral for 1P, line-to-line for 3P.
3. Set the power factor (1 for resistive, lower for motors).
4. Choose the phase system.
5. Read the result. Watts, kW and kVA together.
6. Export the conversion if you need to keep it.

Example 1 — Resistive heater. 13 A at 230 V, unit pf: 2,990 W = 2.99 kW.

Example 2 — Motor. 20 A at 400 V three-phase with pf 0.86: 20 x 400 x 1.732 x 0.86 ≈ 11.9 kW.

Example 3 — Circuit check. A 16 A single-phase outlet at 230 V unit pf carries up to 3.68 kW.

Example 4 — Appliance rating. A 10 A device on 230 V residential supply: 2.3 kW rated.

• Correct conversions: Power factor and phase accounted for, not ignored.
• Dual output: Real power (kW) and apparent (kVA) both visible.
• Explained maths: The formula line shows exactly how the number was built.
• Export ready: Text, CSV and JSON for your records.
• Free and private: No uploads, no accounts, no logging.