Ohm's Law Calculator
Calculate voltage, current or resistance.
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Free electrical, power, battery, resistance and technical calculators.
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Power, Voltage & Current
kW, kVA & Energy
Batteries & DC
Resistance, LEDs & Circuits
Frequency, Capacitance & Inductance
Power, Voltage & Current
Back to top ↑Watts Volts Amps Calculator
Calculate one electrical value from the other two.
Open ToolWatts to Amps Calculator
Convert watts to amps using voltage.
Open ToolAmps to Watts Calculator
Convert amps to watts using voltage.
Open ToolVolts to Watts Calculator
Calculate watts from volts and amps.
Open ToolKilowatts to Amps Calculator
Convert kW to amps for single phase.
Open ToolAmps to Kilowatts Calculator
Convert amps to kW for single phase.
Open ToolSingle Phase Power Calculator
Calculate single-phase power.
Open ToolThree Phase Power Calculator
Calculate three-phase power.
Open ToolPower Factor Calculator
Calculate power factor from real and apparent power.
Open ToolkW, kVA & Energy
Back to top ↑kVA to kW Calculator
Convert kVA to kW using power factor.
Open ToolkW to kVA Calculator
Convert kW to kVA using power factor.
Open ToolkVA to Amps Calculator
Convert single-phase kVA to amps.
Open ToolAmps to kVA Calculator
Convert single-phase amps to kVA.
Open ToolElectrical Energy Calculator
Calculate kWh from power and time.
Open ToolElectricity Cost Calculator
Estimate electricity cost.
Open ToolJoules to Watt Hours Calculator
Convert joules to watt-hours.
Open ToolWatt Hours to Joules Calculator
Convert watt-hours to joules.
Open ToolBatteries & DC
Back to top ↑Watt Hours to Amp Hours Calculator
Convert Wh to Ah using voltage.
Open ToolAmp Hours to Watt Hours Calculator
Convert Ah to Wh using voltage.
Open ToolBattery Runtime Calculator
Estimate battery runtime.
Open ToolBattery Charge Time Calculator
Estimate battery charge time.
Open ToolSeries Battery Voltage Calculator
Calculate total voltage of batteries in series.
Open ToolParallel Battery Capacity Calculator
Calculate total Ah in parallel.
Open ToolResistance, LEDs & Circuits
Back to top ↑Series Resistor Calculator
Calculate total resistance in series.
Open ToolParallel Resistor Calculator
Calculate total parallel resistance.
Open ToolLED Resistor Calculator
Calculate LED series resistor value.
Open ToolVoltage Divider Calculator
Calculate voltage divider output.
Open ToolResistor Power Calculator
Calculate resistor power.
Open ToolVoltage Drop Calculator
Estimate DC voltage drop.
Open ToolCable Voltage Drop Percentage Calculator
Calculate voltage drop percentage.
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