Free Resistor Color Code Calculator

Trying to decipher the painted color bands on a tiny resistor can be a frustrating and error-prone process. Our free, real-time Resistor Color Code Calculator allows you to quickly translate those colors into accurate resistance values, tolerances, and temperature coefficients for 4-band, 5-band, and 6-band resistors.

How to Read a Resistor (Left to Right)

To use this calculator effectively, you first need to know which direction to read your physical resistor. Hold the component so that the cluster of bands is grouped to the left. The single band sitting by itself on the far right is the tolerance band (typically Gold, Silver, or Brown). You will read the colors from left to right.

How to Use the Calculator

1. Select the Number of Bands: Count the color stripes on your resistor and select the 4-Band, 5-Band, or 6-Band toggle at the top of the tool. The input fields will adapt automatically.
2. Enter the Significant Digits: Use the dropdown menus to match the colors of the first 2 (or 3) bands on your resistor. These represent the base numerical value.
3. Select the Multiplier: Match the color of the multiplier band. This tells the calculator how many zeros to add to your base number (or what decimal to multiply by).
4. Select the Tolerance: Match the color of the final, separated band. This determines the manufacturing accuracy of the resistor (e.g., ±5%).
5. View Instant Results: There is no need to click a calculate button! As you change the colors, the tool automatically calculates the exact Resistance Value in real-time, converting it seamlessly into Ohms (Ω), kilo-Ohms (kΩ), Mega-Ohms (MΩ), or Giga-Ohms (GΩ).
6. Copy Your Data: Click the "Copy Results" button to instantly save the calculated specifications to your clipboard for easy pasting into your notes or schematics.