Ohm's Law Calculator
Calculate voltage (V), electric current (I), electrical resistance (R), and total power dissipation (P) in DC electrical circuits.
Ohm's Law Calculator
Calculate voltage, current, resistance, and power
⚡ Voltage (V)
12
🔌 Current (A)
2
🔧 Resistance (Ω)
6
💡 Power (W)
24
Formulas
Understanding Ohm's Law & Circuit Calculations
Formulated by German physicist Georg Ohm in 1827, Ohm's Law dictates that the electric current flowing through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance.
The Ohm's Law Matrix Formulas
Voltage (V)
V = I × R
Current (I)
I = V ÷ R
Resistance (R)
R = V ÷ I
Manual Step-by-Step Circuit Calculation
Suppose an electrical appliance operates on a 120 Volts (V) power supply with a circuit resistance of 24 Ohms (Ω):
- Calculate Current (I): I = V ÷ R = 120 ÷ 24 = 5 Amperes (A).
- Calculate Power (P): P = V × I = 120 × 5 = 600 Watts (W).
Frequently Asked Questions
What is the difference between Direct Current (DC) and Alternating Current (AC)?
Direct Current (DC) flows continuously in one direction (found in batteries and solar panels). Alternating Current (AC) periodically reverses direction (found in household wall outlets). Ohm's Law applies directly to DC and purely resistive AC circuits.
What happens to current if resistance increases?
If voltage remains constant, increasing resistance reduces the current flow proportionally. If resistance doubles, current is halved.
Save Configuration Snapshot
Save current parameters to your dashboard for instant one-click reloading.
About This Calculator & Guide
About the Ohm's Law— Voltage, Current, Resistance & Power Calculator
The Ohm's Law— Voltage, Current, Resistance & Power Calculator is a specialized online utility designed to help you calculate voltage (v), current (i), resistance (ω), and power (w) using ohm's law equations. includes step-by-step circuit examples and formulas. It performs calculations in real-time to provide immediate, reliable estimates for study, work, or daily tasks.
How to Use
Simply enter your parameters in the input fields of the calculator widget above. The tool evaluates the inputs instantly and displays the results in real-time. You can modify any value to check alternate scenarios and compare figures dynamically.
Data Privacy & Safety
All calculations are executed locally within your web browser. No inputs are sent to our servers or stored externally, ensuring your personal and financial details remain completely private and secure.
FAQ
Frequently Asked Questions
What is Ohm's Law and its mathematical formula?+
Ohm's Law defines the relationship between Voltage (V), Current (I), and Resistance (R) in an electrical circuit: Voltage = Current × Resistance (V = I × R).
How do you calculate electrical power in watts using Ohm's Law?+
Electrical Power (P in watts) is calculated by multiplying Voltage (V in volts) by Current (I in amperes): P = V × I. Alternatively, P = I² × R or P = V² / R.
What units are used in Ohm's Law?+
Voltage is measured in Volts (V), Current in Amperes or Amps (A), Resistance in Ohms (Ω), and Power in Watts (W).