# Ohm’s Law Calculator – P, I, V, R Calculator

## Ohm’s Law Calculator – Power, Current, Voltage & Resistance Calculator

Below are the four Electrical calculators based on Ohm’s Law with Electrical Formulas and Equations of Power, Current, Voltage and Resistance in AC and DC Single phase & Three Phase circuit.

Enter the known values and select a conversion from the buttons below and click on Calculate. result will display the desire values which you want to calculate.

### Power Calculator

Calculate Power (W) in Watts using Ohm’s Law:
Enter any two values of: V, I, and R
 V: I: R: Watts (W):

#### Electrical Power Formulas

Electrical Power formulas in DC Circuits

• P = VxI
• P = I2R
• P = V2/R

Electrical Power formulas in Single Phase AC Circuits

• P = VxI Cosθ
• P = I2 x R Cosθ
• P = (V2/R) Cosθ

Electrical Power formulas in Three Phase AC Circuits

• P =√3 x VLxIL Cosθ
• P =3 x VPxIP Cosθ
• P =3 I2 x R Cosθ
• P =3 (V2/R) x R Cosθ

Where

• I = Current in Amperes (A)
• V = Voltage in Volts (V)
• P = Power in Watts (W)
• R = Resistance in Ohm (Ω)

Related Post: Power, Voltage, Current and Resistance Calculator

### Current Calculator

Calculate Current (I) in Amperes using Ohm’s Law:
Enter any two values of: V, W, and R
 V: W: R: 3-Phase Amperes (A):

#### Electrical Current Formulas

Electrical Current Formulas in DC Circuit

• I=V/R
• I = P/V
• I = √P/R

Electrical Current Formulas in Single Phase AC Circuit

• I = P / (V x Cosθ)
• I = (V/Z)…Where Z = impedance = Resistance of AC Circuits

Electrical Current Formulas in Three Phase AC Circuit

I = P / √3xVxCosθ

Where

• I = Current in Amperes (A)
• V = Voltage in Volts (V)
• P = Power in Watts (W)
• R = Resistance in Ohm (Ω)

Related Calculator: RMS Voltage Calculator – From Average Value, Peak & Peak to Peak Value

### Voltage Calculator

Calculate Voltage (V) in Volts using Ohm’s Law:
Enter any two values of: W, I, and R
 W: I: R: Volts (V):

#### Voltage or Electrical Potential Formulas

Electrical Potential or Voltage Formula in DC Circuits

• V = I x R
• V = P / I
• V = √ (P x R)

Voltage or Electrical Potential Formulas in Single Phase AC Circuits

• V = P/(IxCosθ)
• V = I / Z… Where Z = impedance = Resistance of AC Circuits

Where

• I = Current in Amperes (A)
• V = Voltage in Volts (V)
• P = Power in Watts(W)
• P = Power in Watts(W)
• R = Resistance in Ohm (Ω)

Related Calculator: Standard Resistor Closest Value Calculator

### Resistance Calculator

Calculate Resistance (R) in Ohms (Ω) using Ohm’s Law:
Enter any two values of: V, I, and W
 V: I: W: R (Ohms = Ω):

#### Electrical Resistance Formulas

• R = V/I
• R = P/I2
• R = V2/P

Where

• I = Current in Amperes (A)
• V = Voltage in Volts (V)
• P = Power in Watts (W)
• R = Resistance in Ohm (Ω)