6 Band Resistor Calculator
Calculate the resistance of a 6 band resistor
Resistance Calculator
6 Band Resistor
Outputs
Resistance:????
Tolerance:????
Tempco:????
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.
6 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 6 band resistor:
Band 1 ?￠???? first significant digit.
Band 2 ?￠???? second significant digit
Band 3 ?￠???? third significant digit
Band 4 ?￠???? Multiplier
Band 5 ?￠???? Tolerance
Band 6 ?￠???? Temperature Coefficient (Tempco)
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 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
Resistance Temperature Coefficient
Resistors values can change with temperature. The 6th band represents the temperature coefficient or tempco and is represents the amount the resistance value will change with temperature. It is in units of ppm/degree C. The band colors represents the following:
brown ?￠???? 100 ppm/???????oC
red ?￠???? 50 ppm/???????oC
orange ?￠???? 15 ppm/???????oC
yellow ?￠???? 25 ppm/???????oC
blue ?￠???? 10 ppm/???????oC
violet ?￠???? 5 ppm/???????oC
An example if a resistor had a nominal value of 1K ohm and a tempco of 100 ppm/???????oC and we wanted to know how much a resistor would change of 25???????oC.
100*25/1e6*1K= 2.5 ohm variation over 25???????oC.