Electrical Unit Converter — Volts, Amps, Ohms, Farads & More

The Formula

Electrical unit conversion uses linear factors relative to SI base units per sub-category (V, A, Ω, F, H, S, C). All units within a sub-category share the same physical quantity and convert linearly. Converting between sub-categories (e.g., volts to amps) is not physically meaningful without additional circuit context. For example, converting 1 kV to MV: 1 kV × 1000 ÷ 1,000,000 = 0.001 MV. The V·A = W relationship (power = voltage × current) requires knowing both values and is a different calculation.

Variable Definitions

How to Use This Calculator

1. 1

   Enter the electrical value you want to convert in the "Value" field.

2. 2

   Select the current unit from the "From" dropdown. Units are grouped by measurement type (Voltage, Current, Resistance, etc.).

3. 3

   Select the desired unit from the "To" dropdown. Convert within the same measurement type for physically meaningful results.

4. 4

   The converted value is displayed instantly. Use this for circuit design, component selection, or electrical engineering calculations.

5. 5

   Use the quick reference table for common electrical unit relationships and component value conversions.

Quick Reference

Common Applications

• Household voltage: 120 V (US) / 230 V (Europe)
• USB power: 5 V, up to 3 A (15 W standard)
• ResistorAn electrical component that opposes current flow. Resistance is measured in ohms (Ω) and follows Ohm's Law.: 4.7 kΩ with gold band = 4,700 Ω ±5%
• Capacitor labeled "104": 10 × 10⁴ pF = 100 nF = 0.1 µF
• Phone battery: 3,000–5,000 mAh at 3.7–3.8 V
• Power line: 138–765 kV (transmission) / 120–240 V (residential)

V = I × R | I = V ÷ R | R = V ÷ I | Power = V × I

Understanding the Concept

Electrical quantities come in several fundamental types — voltage (V), current (A), resistance (Ω), capacitance (F), inductance (H), conductance (S), and charge (C). Each has its own SI base unit and a range of metric prefixes from micro (µ, millionth) to kilo (k, thousand) to mega (M, million) and beyond. Understanding electrical unit conversion is essential for electronics design, electrical engineering, power systems, and even everyday tasks like reading a component's markings or sizing a power supply. A resistor marked "4.7 kΩ" is 4,700 ohms. A capacitor labeled "100 nF" is 0.1 µF or 100,000 pF. A phone battery rated at 3,000 mAh holds 10,800 coulombs of charge. A power line operating at 138 kV carries 138,000 volts. The relationships between these quantities are governed by Ohm's LawThe relationship between voltage (V), current (I), and resistance (R): V = I × R. The fundamental law of electrical circuits. (V = IR), Watt's Law (P = VI), and the fundamental equations of electromagnetism. While this converter handles conversions within each measurement type, remember that volts and amps are different physical quantities and cannot be directly converted — that would be like converting meters to kilograms.

Frequently Asked Questions

Sources & References