Table of Content

• Resistor Colour Code
• Resistor Colour Table
• How to Read Resistor Colour Code?
• Example of Resistor Colour Coding
• Mnemonic of Resistor Colour Code
• Resistor Colour Code Examples

Colour	Colour Representation	Digit	Multiplier	Tolerance
Black		0	1
Brown		1	10	± 1%
Red		2	100	± 2%
Orange		3	1000
Yellow		4	10,000
Green		5	100,000	± 0.5%
Blue		6	1,00,000	± 0.25%
Violet		7	10,000,000	± 0.1%
Grey		8		± 0.05%
White		9
Gold			0.1	± 5%
Silver			0.01	± 10%

How to Read Resistor Colour Code?

The color code in any resistor is read as, in general, a resistor has four bands in which the first two bands represent the value of the resistance and the third band represent the resistance multiplier whereas, the fourth and the last band represent the tolerance of the resistance. For reading any resistance we hold the resistor in such a way that its tolerance band is to our right. generally, the tolerance is silver and gold in colour and it is at a distance from the other band.

Now starting from our left, mark all the colors of the bands and write them down in sequence. Then, use the table given above to see which digits they represent.

The third band is the multiplier band and the colour represents the 10 multipliers. Such as if the third band is green then its value is 10⁵. 

Example of Resistor Colour Coding

The resistor color coding is used to determine the value of the resistance of the electrical resistor. This can be understood using the example discussed below as, 

The image added below shows resistance and using resistor colour coding determines its resistance value.

The band colors for the resistor color code in the order:

Band colours in order RED ORANGE ORANGE GOLD

Using the table the digit representation is as 2 2 3 with multiplier 10³ and the tolerance ±5%

Thus, the value of the resistance is, 23×10³ Ω ± 5 %

i.e. the value of the resistance is, 23000 Ω ± 5 %

The value of the given resistance is:

23000 Ω ± 5 %. The tolerance of the resistor can be calculated as follows:

Tolerance = Value of Resistor × Value of Tolerance Band

= 23000 Ω ⨯ 5 % = 1150 Ω

This means that the 23000 Ω resistor with a tolerance value of 1150 Ω could range from the actual value as much as 24150 Ω to as little as 22850 Ω. 

Mnemonic of Resistor Colour Code

Learning the Resistor Color Coding is very important and the mnemonic used to find the value of the resistor is,

BB ROY of Great Britain had a Very Good Wife

The capital letters represent the first letters of the colors and their positions in the digit values. The representation of the color code as,

Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, and White

Read More,

• Electrical Resistance
• Equivalent Resistance
• Resistivity

Resistor Colour Code Examples

Example 1: Find the resistance of the resistor

Solution:

The band colours for resistor colour code in the order:

Band colours in order RED RED ORANGE SILVER

using the table the digit representation is as, 2 2 3 and the tolarence is ±10%

Thus, the value of the resistance is, 22×10³ Ω ± 10 %

i.e. the value of the resistance is, 22000 Ω ± 10 %

The value of the given resistance is:

22000 Ω ± 10 %. The tolerance of the resistor can be calculated as follows:

Tolerance = Value of Resistor × Value of Tolerance Band

=  22000 Ω ⨯ 10 % = 2200 Ω

This means that the 22000 Ω resistor with a tolerance value of 2200 Ω could range from the actual value as much as 19800 Ω to as little as 24200 Ω. 

Example 2: Find the resistance of the resistor,

Solution:

The band colours for resistor colour code in the order:

Band colours in order ORANGE RED BLACK SILVER

using the table the digit representation is as, 3 2 1 and the tolarence is ±10%

Thus, the value of the resistance is, 32×10¹ Ω ± 10 %

i.e. the value of the resistance is, 32 Ω ± 10 %

The value of the given resistance is:

32 Ω ± 10 %. The tolerance of the resistor can be calculated as follows:

Tolerance = Value of Resistor × Value of Tolerance Band

=  32 Ω ⨯ 10 % = 3.2 Ω

This means that the 32 Ω resistor with a tolerance value of 3.2 Ω could range from the actual value as much as 28.8 Ω to as little as 35.2 Ω. 

Conclusion of Resistor Colour Code

The resistor color code is a standardized system used to indicate the resistance value, tolerance, and sometimes the temperature coefficient of a resistor. By examining the color bands on a resistor, one can determine its resistance value according to the color code chart.

Resistor Colour Code – FAQs

Why are Resistors Color Coding done?

Resistor are very small electronic devices and it is very difficult to print values on the resistor and so we use color bands to represent the value of the electrical resistance. 

How does Resistor Color Code work?

There are various bands of color added to the resistor that are used to represent the values of the resistance, generally a resistor has three to six bands. In general, for a resistor with five bands the first three bands represent the significant digits, the fourth band is the multiplying factor and the fifth band represents the tolerance.

What is the Trick to Remember Resistor Color Code?

We use the mnemonics to learn the Resistor Colour Code as, 

“BB ROY of Great Boy had a Very Good Wife,” the capital letters represent the first letters of the colors and their positions in the digit values, i.e. Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, and White.

What is Color Code of a Resistor?

A resistor with a colour code is used to represent the value of the resistor. In a resistor with five bands, the first three bands indicate the significant digits, the fourth band is the multiplication factor, and the fifth band represents the tolerance.

Who Invented Resistor Colour Code?

The Resistor Colour Code was developed by the Radio Manufacturers Association (RMA) in the 1920s.