Resistor Color Codes and Standard Resistor Values

Resistors are read starting from the line closest to the end of the resistor.  They will either have 4 bands or 5 bands.  If there are four bands then the first two are the value, the third is the multiplier, and the fourth is the precision.  If there are five bands then the first three are the value, the fourth is the multiplier, and the fifth is the precision.

Color  1st Digit (A)  2nd Digit (B)   Multiplier (C) Tolerance (D) 
 Black  0  1 1% 
 Brown  1  1  10  2%
 Red  2  2  100  3%
 Orange  3  3  1000  4%
 Yellow  4  4  10000  
 Green  5  5  100000  0.5%
 Blue  6  6  1000000  0.25%
 Violet  7  7  10000000 0.10% 
 Gray  8  8  100000000  0.05%
 White  9  1000000000  
 Gold      0.1  5%
 Silver      0.01  10%
 No Color        20%

Resistors are read starting from the line closest to the end of the resistor.  They will either have 4 bands or 5 bands.  If there are four bands then the first two are the value, the third is the multiplier, and the fourth is the precision.  If there are five bands then the first three are the value, the fourth is the multiplier, and the fifth is the precision.

 

For example take the following resistor which has bands GreenBlueYellow, and Gold.  Since there are four bands the third band is the multiplier and the fourth band is the tolerance.  Looking at the chart below:

Green = 5 (tens place)

Blue = 6 (ones place)

Yellow = 10KΩ

Gold = 5%

Understanding the value.  Put the 5 and 6 together for 56 then multiply by 10KΩ - 56*10KΩ=560kΩ.

Understanding the tolerance.  The tolerance is +/-5% - 560kΩ*5%=28kΩ which means the resistor may be 28kΩ lower or higher than the stated value.    560kΩ-28kΩ=532kΩ.  560kΩ+28kΩ=588kΩ.  So the acceptable resistance of this resistor is between 532KΩ and 588KΩ.

resistorchart.png

Above is an example of a 5 band resistor.  They are usually higher precision resistors.  In this case the band colors are redorangevioletblack, and brown.

Red = 2 (hundreds place)

Orange = 3 (tens place)

Violet = 7 (ones place)

Black = 1Ω

Brown = 1%

237Ω 1%

Mnemonics for remembering color codes.  Mnemonics are the only way I can remember the color codes but times have changed in the 20+ years since my instructor told me the mnemonic for remembering resistor color codes and it would be too offensive for this site today.  However when I began researching modern mnemonics used to remember resistor color codes in schools I didn't find any of them nearly as effective.  So here is a good list of various mnemonics for remembering resistor color codes from Wikipedia.

https://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics

 

Standard Resistor Values for 5% Tolerance

1.0   

 9.1   91  750 6.2k  51k  430k  3.9M 
 1.1  12  100  820  6.8k  56k  470k  4.3M
 1.2  13  110  910  7.5k  62k  510k  4.7M
 1.3  15  120  1.0k  8.2k  68k  560k  5.1M
 1.5  16  130  1.1k  9.1k  75k  620k  5.6M
 1.6  18  150  1.2k  10k  82k  680k  6.2M
 1.8  20  160  1.3k  11k  91k  750k  6.8M
 2.0  22  180  1.5k  12k  100k  820k  7.5M
 2.2  24  200  1.6k  13k  110k  910k  8.2M
 2.4  28  220  1.8k  15k  120k  1.0M  9.1M
 2.7  30  240  2.0k  16k  130k  1.1M  10.0M
 3.0  33  270  2.2k  18k  150k  1.2M  
 3.3  36  300  2.4k  20k  160k  1.3M  
3.9   39  330  2.7k  22k  180k  1.5M  
 4.3  43  360  3.0k  24k  200k  1.6M  
 4.7  47  390  3.3k  27k  220k  1.8M  
 5.1  51  430  3.6k  30k  240k  2.0M  
 5.6  56  470  3.9k  33k  270k  2.4M  
 6.2  62  510  4.3k  36k  300k  2.7M  
 6.8  68  560  4.7k  39k  330k  3.0M  
 7.5  75  620  5.1k  43k  360k  3.3M  
 8.2  82  680  5.6k  47k  390k  3.6M  

k = kilohms = 1,000 ohms

m = megohms = 1,000,000 ohms 

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