Electrical Calculator

Professional electrical calculations for circuits and power systems

Quick answer

Electrical Calculator

Calculate voltage, current, resistance, and power using Ohm's Law and power formulas. Essential for electrical work and circuit analysis.

Formula

V = I × R (Ohm's Law), P = V × I (Power)

⚡ Electrical Calculations

🔌 Results

Enter values and click Calculate to see results

⚡ Quick Reference

Ohm's Law: V = I × R

Power: P = V × I = I²R = V²/R

Energy: E = P × t (Wh or kWh)

Note: Enter any 2 values to calculate the rest

⚡Formula

V = I × R (Ohm's Law), P = V × I (Power)

💡How it works

Calculate voltage, current, resistance, and power using Ohm's Law and power formulas. Essential for electrical work and circuit analysis.

ℹ️ What is Electrical Calculator?

An electrical calculator applies fundamental electrical laws — Ohm's Law, Watt's Law, and Kirchhoff's Laws — to compute voltage, current, resistance, and power in circuits. It is used by electricians, engineers, students, and hobbyists for sizing wires, fuses, and components.

📐 Formula

Ohm's Law: V = I × R | Power: P = V × I = I² × R = V² / R
V— Voltage in volts (V)
I— Current in amperes (A)
R— Resistance in ohms (Ω)
P— Power in watts (W)

✏️ Worked Example

Voltage: 120 V
Resistance: 60 Ω
  1. 1Current: I = V / R = 120 / 60 = 2 A
  2. 2Power: P = V × I = 120 × 2 = 240 W
  3. 3Check: P = I²R = 4 × 60 = 240 W ✓
✅ Result: Current = 2 A | Power = 240 W

💡 How to Interpret Results

  • ▸If current × resistance drops across all components sum to supply voltage (Kirchhoff's Voltage Law).
  • ▸Higher resistance means lower current for the same voltage — useful for limiting current to LEDs and components.
  • ▸Power dissipated as heat in a resistor: higher I and higher R both increase heat (P = I²R).
  • ▸For AC circuits, use impedance (Z) instead of pure resistance for power factor corrections.
  • ▸Always verify wire gauge can handle the calculated current — undersized wire overheats and is a fire hazard.

❓ Frequently Asked Questions

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