Five-Color-Ring Resistor Calculator

1st
Digit

2nd
Digit

3rd
Digit

Multi-
plier

Toler-
ance

Black

Brown

x10

± 1%

Red

x100

± 2%

Orange

x1K

± 3%

Yellow

x10K

± 4%

Green

x100K

± 0.5%

Blue

x1M

± 0.25%

Violet

x10M

± 0.10%

Grey

x100M

± 0.05%

White

x1G

Gold

÷ 10

± 5%

Silver

÷ 100

± 10%

Outputs

Resistance:

Tolerance:

Introduction

A resistor is a perhaps the most common building block used in circuits. Resistors come in many shapes and sizes this tool is used to decode information for color banded axial lead resistors.

5 Band Description

The number of bands is important because the decoding changes based upon the number of color bands. There are three common types: 4 band, 5 band, and 6 band resistors. For the 5 band resistor:

Band 1 – First significant digit.
Band 2 – Second significant digit
Band 3 – Third significant digit
Band 4 – Multiplier
Band 5 – Tolerance

Resistance Value

The first 4 bands make up the resistance nominal value. The first 3 bands make up the significant digits where:
black – 0
brown – 1
red – 2
orange – 3
yellow – 4
green – 5
blue – 6
violet – 7
grey – 8
white – 9

The 4th band or multiplier band is color coded as follows:
black – x1
brown – x10
red – x100
orange – x1K
yellow – x10K
green – x100K
blue – x1M
violet – x10M
grey – x100M
white – x1G
gold – .1
silver – .01

An example of a resistance value is:

band 1 = orange = 3,
band 2 = yellow = 4,
band 3 = green = 5,
band 4 = blue = 1M

value = 345*1M = 345 Mohm

Resistance Tolerance

The fifth band is the tolerance and represents the worst case variation one might expect from the nominal value. The color code for tolerance is as follows:
brown – 1%
red – 2%
orange – 3%
yellow – 4%
green – .5%
blue – .25%
violet – .1%
gray – .05%
gold – 5%
silver – 10%

An example calculating the range of a resistor value is:

If the nominal value was 345 Ohm and the 5th band of the resistor was gold (5%) the value range would be nominal +/- 5% = 327.75 to 362.25