Enter any two values of V, I, and R (use consistent units), then click calculate to get the third.
Ohm’s Law describes the linear relationship among voltage, current, and resistance. If you know any two of V, I, or R, you can compute the third with V = I × R.
Standard units are volts (V), amperes (A), and ohms (Ω). Keeping units consistent ensures your result has physical meaning.
This calculator is useful for component selection, power supply matching, and quick checks during circuit troubleshooting.
Ohm’s Law applies to linear resistive elements. Nonlinear devices like diodes and transistors require their own characteristic curves.
If your result seems off, verify input units, measurement conditions, and temperature effects on resistance.
Using Ohm’s Law correctly saves time and reduces trial-and-error in electrical design and learning.
V = I × R.
Volt (V).
Ampere (A).
Ohm (Ω).
I = V ÷ R.
R = V ÷ I.
V = I × R.
It mainly applies to linear resistive elements; nonlinear devices need their own curves.
Inconsistent units lead to incorrect results and invalid physical meaning.
Circuit design, power estimation, supply matching, and troubleshooting.
Quickly convert between voltage, current, and resistance for study, design, and troubleshooting.
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