What is the Resistor Color Code Calculator?
This tool is an online simulator designed to instantly calculate the resistance value (Ohms) and tolerance of a resistor based on its color bands. It is widely used in electronics and circuit design to verify values without performing manual calculations.
How to Read 4-Band Resistor Codes
The 4-band resistor is calculated using the following formula:
((1st Digit × 10) + 2nd Digit) × Multiplier
| Resistance Example | 4-Band Color Pattern |
|---|---|
| 1kΩ | Brown, Black, Red, Gold |
| 10kΩ | Brown, Black, Orange, Gold |
| 470Ω | Yellow, Violet, Brown, Gold |
Features of This Tool
- Completely Free: Access all features at no cost.
- No Registration: No account or login required.
- Privacy-Focused: All calculations are done locally in your browser; data is never sent to a server.
Steps to Use
- Identify the color bands on the resistor, starting from the side where the bands are closer to the end.
- Select the colors for the 1st and 2nd bands from the dropdown menus.
- Select the "Multiplier" (3rd band).
- Select the "Tolerance" (4th band). Gold and Silver are the most common colors here.
- The calculated value will appear in real-time in the blue box.
Frequently Asked Questions (FAQ)
Q. How do I tell which band is the "1st band"?
A. Generally, the side where the bands are closer together is the start (left side). The 4th band (tolerance) is often spaced further apart from the other three.
Q. What is the value of Brown-Black-Black-Gold?
A. Brown(1) - Black(0) × Black(1x multiplier) = 10Ω.
Q. Can I calculate 5-band resistors here?
A. This tool is specifically for 4-band resistors. For precision resistors with 5 bands, please use our dedicated 5-band calculation page.