About the Resistance Calculator
Resistance from voltage and current (R = V/I), in ohms.
Also known as: ohms calculator, find resistance, r = v/i, resistor value.
How to use this calculator
- Enter solve for.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
R = V / I
Worked example
Using the values pre-filled in the calculator above:
- Solve for: Resistance
- Voltage = 5 V
- Current = 0.05 A
the calculator returns:
- Resistance: 100 Ω
- Voltage: 5 V
- Current: 0.05 A