A handy tool for reading resistor color code values

4 strip Resistor

1st Digit
2nd Digit
Multiplier
Tolerance

ohms
 
ohms
ohms

5 strip Resistor

1st Digit
2nd Digit
3rd Digit
Multiplier
Tolerance

ohms
 
ohms
ohms

6 strip Resistor

1st Digit
2nd Digit
3rd Digit
Multiplier
Tolerance
Tempco

ohms
 
ohms
ohms
ppm/°C

Overview

Are you having trouble reading resistor color codes? If your answer is yes, then this tool is specifically designed for you! Our Resistor Color Code Calculator is a handy tool for reading carbon-composition resistors whether it's a 4-band, 5-band or 6-band type. 

To use this tool, simply click on a particular color and number and watch how the actual bands on the resistor illustration change. The resistance value is displayed on the field below together with the tolerance and the temperature coefficient.  

Notes

As shown above, a carbon-composition resistor can have 4 to 6 bands. A 5-band resistor is more precise compared to a 4-band type because of the inclusion of a third signficant digit. A 6-band resistor is like a 5-band resistor but includes a temperature coefficient band (the 6th band). 

  4-band 5-band 6-band
1st band 1st significant digit 1st significant digit 1st significant digit
2nd band 2nd significant digit 2nd significant digit 2nd significant digit
3rd band multiplier 3rd significant digit

3rd significant digit

4th band tolerance multiplier multiplier
5th band N/A tolerance tolerance
6th band N/A N/A temperature coefficient

Each color represents a number if it's located from the 1st to 2nd band for a 4-band type or 1st to 3rd band for a 5-band and 6-band type. 

Color Value

Black (2nd and 3rd bands only)

0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Grey 8
White 9

 

Mnemonics were created to easily memorize the sequence of the colors. The most popular mnemonic is "Big Boys Race Our Young Girls But Violet Generally Wins" where the first letter of each word corresponds to the first letter of the color. 

If the color is found on the 3rd band for a 4-band type or the 4th band for a 5-band and 6-band type, then it's a multiplier.

Color Value

Black

x1
Brown x10
Red x100
Orange x1000
Yellow x10000
Green x100000
Blue x1000000
Violet x10000000
Grey x100000000
White x1000000000

Notice that the number of zeroes is equal to the color's number as per the previous table.

The fourth band (or 5th for the 5-band and 6-band) indicates the tolerance values. Here, two colors are added (gold and silver).

Color Value

Black

N/A

Brown ±1%
Red ±2%
Orange ±3%
Yellow ±4%
Green ±0.5%
Blue ±0.25%
Violet ±0.15%
Grey ±0.05%
White N/A
Gold ±5%
Silver ±10%

The 6th band for a 6-band type resistor is the temperature coefficient. This indicates how much the actual resistance value of the resistor changes when the temperature changes.

Color Value

Black

N/A
Brown 100 ppm/ºC
Red 50 ppm/ºC
Orange 15 ppm/ºC
Yellow 25 ppm/ºC
Green N/A
Blue 10 ppm/ºC
Violet 5 ppm/ºC
Grey N/A
White N/A


Further Reading

Textbook - Resistor: Ohm's Law

Textbook - Resistor Color Codes

Worksheet - Resistors

Comments

13 Comments


  • ilane 2016-04-29

    Yep. Those were the days. I’ll never forget the basics of this. Some of the stuff, though, is esoteric as hell. Who’d make these days a ±0.05% tolerance resistor and mark it with color bands? Who has ever made one?

  • col_panek 2016-11-05

    Funny, I never heard that mnemonic, but something similar which I won’t repeat.

  • Eugene Edwards 2016-12-22

    I find this to be extremely helpful it’s about to save me $250.00 because now I can replace the resistor I fried on my electric board instead of buying a whole new board I’m so grateful to finally find a site that gives detailed information on electronics no one in this area wants to learn it so colleges have not had the class available thank you very much

  • Yahiko 2016-12-23

    I would like a version that I can have on my computer because I don’t always have a connection.

  • ray.leiter 2017-01-21

    Why would anyone go to the trouble of developing an application this useful and not provide a tolerance setting of 20%—it make NO sense!

  • Jari 2017-02-03

    Your calculator is not correct!
    0.1% qn 200K is not 220K is comes to 200.2K or 199.9L on the minus side.
    Hreetings John.

    • RK37 2017-02-03

      Hi Jari, I cannot quite understand your comment. Can you explain the problem in a different way?

      • iwasawizard 2017-02-22

        If you calculate a 200K resistor with a tolerance of 0.1%, the calculator will give a tolerance floor of 180K and a ceiling of 220K, which is correct for 10% tolerance, not 0.1%. The correct tolerance limits should be 199.8K - 200.2K.

  • Robert Keim 2017-02-23

    Ah, thanks for clarifying that, iwasawizard. We fixed it.

  • Jatrik Maity 2017-05-20

    how can I choose ist band inthe case 5 or 6 band

  • Jatrik Maity 2017-05-20

    How can I select 1st band among 5 bands

  • roper_ni 2017-08-09

    should make a downloadable version!
    roper_ni

  • Shimmering Blaze 2017-09-01

    You have the violet tolerance color in your chart set to 0.15% but in the calculator it is set to 0.10%, which is correct?