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Calcimator

Amps / Watts / Volts Converter

Convert between amps, watts, and volts. Enter any two values to calculate the third, plus energy cost estimates.

Inputs

W
A
V
hrs/day
$/kWh

Results

Watts

1,500 W

≈ 25 laptops

Amps12.5 A
Volts120 V
Daily kWh12 kWh
Monthly Cost$46.80
Annual Cost$569.40
How to Use This Calculator
  1. Enter any two of the three values — Watts, Amps, or Volts — to calculate the third.
  2. Input Daily Usage (hours) to compute daily kilowatt-hours (kWh).
  3. Enter your Electricity Rate ($/kWh) to see the daily and annual operating cost.
  4. Review the calculated Watts and Amps alongside the cost estimates.
  5. Use this to size extension cords, check outlet capacity, or estimate appliance running costs.

How the result changes with Watts

WattsWatts
10,00010,000 W
35,00035,000 W
65,00065,000 W
90,00090,000 W

What each input means

Watts
Power in watts. Leave at 0 to calculate from amps and volts.
Amps
Current in amps. Leave at 0 to calculate from watts and volts.
Volts
Voltage of the circuit (120V standard, 240V heavy appliances).
Daily Usage
Average hours per day the device runs.
Electricity Rate
Local electricity cost per kilowatt-hour.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Watts = 1500, Amps = 0, Volts = 120, Daily Usage = 8 = 5 input(s) provided
  2. Calculate Watts
    Watts
    1500 = 1500
  3. Calculate Amps
    Amps
    12.5 = 12.5
  4. Calculate Volts
    Volts
    120 = 120

Engine last updated .

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