Free Ohm's Law Calculator
Solve for voltage, current, resistance or power.
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Inputs
Result
Voltage
12.000 V
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Short answer
Solve for voltage, current, resistance or power.
What is the Ohm's Law Calculator?
Solve for voltage, current, resistance or power.
How does the Ohm's Law Calculator work?
Enter the inputs above and read the result.
Formula
Variables
VVoltageICurrentRResistance
Explanation
Ohm's law relates voltage, current, and resistance in a simple resistive circuit.
Examples
Applications
Advantages
Limitations
Common mistakes
Tips
Related concepts
The Ohm's Law Calculator sits inside the Everyday & Utility Calculators hub, in the science & electrical cluster. Physics, chemistry and electrical engineering formulas. Understanding the terms below makes the output easier to interpret and easier to compare against neighbouring measures.
Practical use cases and industry applications
Understanding Ohm's Law
Solve for voltage, current, resistance or power. Within everyday & utility calculators, ohm's law belongs to the science & electrical cluster, where it shares terminology and assumptions with closely related tools.
Learning how ohm's law is calculated
Ohm's law relates voltage, current, and resistance in a simple resistive circuit. Working through the variables one at a time — V, I, R — makes the result reproducible by hand and easier to sanity-check.
Using ohm's law to make a decision
Because outputs depend on the assumptions you enter, run more than one scenario before committing to a figure.
How ohm's law compares with related measures
voltage, current, resistance, ampacity all describe adjacent aspects of science & electrical. Comparing this calculator's output against those measures — using the related tools listed on this page — prevents a single metric from being read in isolation.
Frequently asked questions
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