Ohm's Law Calculator
Mutual calculation of voltage, current, resistance, and power
How to Use
- Select a pair of 2 values to input (e.g., V+I, V+R, etc.)
- Enter the values of the selected pair in the input field (you can use SI prefixes)
- The remaining 2 values are automatically calculated and displayed
- The calculation formula used is also displayed
- You can copy the calculation result to the clipboard with the "Copy" button
Use Cases
- When calculating resistance or current values in circuit design
- When calculating the current-limiting resistor for LEDs
- When calculating the power consumption of a power supply
- When checking the ratings of components in electronics projects
Frequently Asked Questions
How do I enter SI prefixes (k, M, etc.)? ▼
Enter the prefix after the number. The supported prefixes are p (pico), n (nano), u (micro), m (milli), k (kilo), M (mega), G (giga), and T (tera). Examples: 4.7k = 4700, 100m = 0.1
Which calculation formula is used? ▼
Based on Ohm's law (V=IR) and the power formula (P=VI), the remaining values are derived from the 2 input values. The specific calculation formula is displayed on the results screen.
How accurate are the calculations? ▼
We use double-precision floating-point numbers (IEEE 754) in JavaScript, which provides sufficient accuracy for typical electronic circuit calculations. The results are displayed in an easy-to-read format using SI prefixes.
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