What is the Ohm’s Law Calculator?
Ohm’s law links voltage (V), current (I) and resistance (R): V = I × R. Together with the power formula P = V × I you can find any two unknowns from the other two. This calculator does it instantly and shows which formula it used.
It is useful for physics students, electronics hobbyists choosing a resistor for an LED, and electricians sizing loads.
How to use the Ohm’s Law Calculator
- Enter any two of the four values (leave the others empty).
- Read the missing values and formulas.
Ohm’s law formulas
- V = I × R, I = V / R, R = V / I
- P = V × I = I² × R = V² / R
Example
A 12 V LED strip drawing 2 A uses P = 12 × 2 = 24 W and has an equivalent resistance of 6 Ω.
This Ohm’s Law Calculator is 100% free, needs no signup and runs privately in your browser – on phone, tablet or computer.
Last updated: · By NodifyTech