What is the Ohm's Law & Power Calculator?
This tool is an online simulator designed to instantly calculate the fundamental relationships of electrical circuits: Ohm's Law and Power. By entering any two of the following—Voltage (V), Current (A), Resistance (Ω), or Power (W)—the remaining values are automatically calculated. It is widely used for DIY electronics, electrical planning, and checking home appliance power consumption.
Ohm's Law Formulas
・Current (I) = Voltage (V) ÷ Resistance (R)
・Resistance (R) = Voltage (V) ÷ Current (I)
About Electric Power (Watts)
Power (P) represents the amount of electrical energy consumed per unit of time.
It is calculated as Power (W) = Voltage (V) × Current (I). Using resistance, it can also be expressed as W = I²R or W = V²/R.
Benefits of This Tool
- Completely Free: All features are available at no cost.
- No Registration: Start calculating immediately without signing up or logging in.
- Secure Design: Calculations happen locally in your browser; your data is never sent to a server.
Frequently Asked Questions (FAQ)
A. The calculator executes based on the values provided. Every time you change a value, the other fields are automatically updated to maintain the relationship.
A. Yes. When working with very small values (like mA or kΩ), please convert them to the base units (Amperes or Ohms) before entry.