What formula converts volts to ohms?

When current is known: R = V / I (Ohm's Law). When power is known: R = V² / P. Both formulas are derived from the fundamental relationship V = I × R.

Voltage in volts (V), current in amperes (A), power in watts (W), and resistance in ohms (Ω).

Can I enter millivolts or milliamps?

Convert to base units first: 500 mV = 0.5 V, 200 mA = 0.2 A. Then enter those decimal values into the calculator.

What happens if current or power is zero?

Division by zero is undefined in both formulas. The calculator will display an error if either divisor is zero.

Does this work for AC circuits?

For AC circuits the result is impedance magnitude rather than pure resistance. Use it as an approximation for purely resistive loads only.

How is this different from an amps-to-ohms calculator?

The underlying formula is the same (R = V / I), but here voltage is the primary input rather than current. Choose the approach that matches which value you know first.

What resistance gives 80 ohms at 120 volts?

Resistance is fixed by the component, not the voltage. At 120 V, an 80 Ω resistor draws I = V / R = 120 / 80 = 1.5 A and dissipates P = V² / R = 120² / 80 = 180 W. To get 80 Ω from this tool, enter 120 V with 1.5 A (R = 120 / 1.5 = 80 Ω).

Volts to Ohms Calculator

Name: Volts to Ohms Calculator
Availability: InStock
Author: Nham Vu

Convert voltage to resistance in ohms using Ohm's Law (R = V / I) or the power formula (R = V² / P).

Enter Values

Voltage (V) *

Calculate using

Current (A)

Enter voltage and current or power, then click Calculate.

Resistance

0 Ω

Formula Applied

Parameter	Value

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