Trigonometry · free · no sign-up
Resistance calculator
Find the resistance of a component from the voltage across it and the current through it.
Resistance calculator
Enter your values below and press Calculate to see your result instantly.
Circuit Parameters (Ohm's Law: V = I × R)
=
Computed Electrical Resistance (R)
6.00 Ω
POWER DISSIPATION (Watts)
24.00 W
CONDUCTANCE LIMIT (G)
0.17 Siemens
Calculations complete.
About the Resistance calculator
Find the resistance of a component from the voltage across it and the current through it.
How to use the Resistance calculator
- Enter the Voltage (V) and Current (I).
- Press Calculate Ohmic Constraint (R).
Formula and method
R = V ÷ I (Ohm's law). Resistance is measured in ohms (Ω).
Worked example
12 V across a component carrying 3 A means a resistance of 4 Ω.
Tips
- Convert milliamps to amps first (divide by 1,000).
- Resistors in series add up; parallel resistors combine as reciprocals.
Frequently asked questions
What is Ohm's law?
The relationship V = I × R between voltage, current and resistance.