A Brief Overview of Resistor Color Codes

Published on July 25, 2024 , Last modified on October 24, 2024
by Hommer Zhao
A Resistor

To begin, resistors are common devices in electronic components and circuits. Besides, you will notice various resistor color codes with a closer look.

These colors represent the total value of the resistor.                

Therefore, It’s important to know the resistor’s value before incorporating it into an electronic component, such as the SAMD21.

This article will help you learn more about resistor color codes and how to identify them.

  

What is the Resistor Code Colour?  

Resistor Color Codes

Resistor Color Codes

Resistor code colors are colored marks printed on resistors to display the electrical resistance and tolerance values.

The resistor’s physical value indicates the wattage rating.

Generally, designers print the tolerance, resistance value, and wattage rating on the resistor’s body as letters or numbers if the resistor is big enough. This is the case with large power resistors.

However, the print is unclear if the resistor is small, for example, in a ¼ watt carbon. Thus, the specifications are shown using resistor color codes. 

How to Identify Resistor Color Code?       

3-Band Resistors: Designers use these resistors when there is a need for a low resistance value.       

For example, a 1Ω resistor with three bands will have colors brown, black, and gold.

In addition, the resistance value for this resistor will fall between 1.2 ohms and 0.8 ohms.                 

4-Band Resistors: These resistors have three color bands located on the left side of the resistor and one on the right.            

The first two color bands represent the resistance, the third represents the multiplier, and the fourth is the tolerance. The 4-band Resistors have tolerances below 20%.       

5-Band Resistors: These resistors have a total of five color bands. The first three bands are the significant digits of resistance.

The fourth is the multiplier, and the fifth color band is the tolerance.         

Besides, an extra band in a 5-band resistor may indicate the reliability of the resistor or the temperature coefficient.

For example, a 270k ohm resistor will have the colors red, violet, black, and orange to represent its value.           

6-Band Resistors: These have six color codes. The first three represent the resistance value.

The fourth, fifth, and sixth are the multiplication factor, the tolerance, and the temperature coefficient, respectively.            

The temperature coefficient gives off the behavior of a resistor under specific heating conditions.

Resistor Color Code Chart

Calculating Resistor Values       

It would help if you read color bands from left to right. Start with the colors and then the multiplier in ohms.       

For example, if a resistor has the color bands yellow, violet, and red, the calculation is as follows:

  • Yellow = 4
  • Violet = 7
  • Red = 10^2

This translates to 47 x 10^2 = 4700Ω. 

Conclusion

This article summarizes the various resistor color codes and how you can calculate the total value. Also, if you have any questions, please get in touch with us on our page.

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Hommer Zhao
Hi, I'm Hommer Zhao, the founder and Chief Editor at WellPCB. With extensive experience in the PCB industry, I oversee all content to ensure it meets the highest standards of accuracy and insight. We proudly serve over 4,000 customers globally. For inquiries or more information, don't hesitate to reach out. Your satisfaction is my top priority!