Engineering

Ohm's Law Calculator

The Ohm's Law calculator solves electrical relationships between voltage, current, resistance, and power.

ohms lawvoltagecurrentresistancepowerelectrical

Calculator

Calculate instantly

Enter any two known positive values. Leave unknown fields blank.

VoltageVV01000CurrentAA0100Resistanceohmsohms010000PowerWW010000

Electrical Values Chart

Derived voltage, current, resistance, and power update live from the known values.

Voltage20 V

Current2 A

Resistance10 ohms

Power40 W

Formula Explanation

V = I x R, P = V x I

Ohm's law states that voltage equals current multiplied by resistance. Power can be derived from voltage and current.

Use Cases

Electrical projects
Circuit analysis
Engineering homework

Step-by-Step Explanation

Step 1Choose the value you want to calculate.
Step 2Enter two known electrical values.
Step 3Apply the relevant Ohm's law or power formula.
Step 4Review the result and related derived values.

Example calculation

Example Ohm's law calculation

Given

Current: 2 A
Resistance: 10 ohms

Steps

Voltage = 2 x 10.
Power = 20 x 2.

Result

Voltage is 20 V and power is 40 W.

Calculator guide

About this Ohm's Law Calculator

Calculate voltage, current, resistance, and power from Ohm's law relationships. This page includes an interactive calculator, concise formula notes, worked examples, FAQs, related calculators, and practical guidance you can revisit whenever needed.

ohms law voltage current resistance power electrical

Found something that does not look right?

We work hard to keep every calculator accurate and useful. If you notice a calculation error, missing option, or unclear explanation, please let us know so we can review and correct it promptly.

Report an Issue

Calculator usage

See how many people are using this calculator.

Total visits today

Live users now

Total saved calculations

Most active date

2026-06-05

FAQ