Resistor colour code table
- the colour code markings used for leaded resistors to mark their value
Resistors are widely used in all areas of electronics. They
are one of the most widely used component, and they are produced in their
billions each year. There is a very large number of standard values of resistor
that can be used, and as a result it is necessary to be able to identify the
value of a resistor.
In view of this it is necessary to have a convenient method
of marking resistors used in electronic circuits that will remain easily visible
at all times. This is the reason for marking resistors with a colour code rather
than marking them with the value in figures. Figures printed onto the resistors
could easily be removed or obscured during handling, or subsequent insertion
into the electronics circuit. Having a resistor colour code using coloured ings
around the component overcomes both these problems.
The resistor colour code bands give the value of the resistor as well as
other information including the tolerance and sometimes the temperature
coefficient. The band closest to the end of the resistor body is taken to be
Band 1. The first two bands of the resistor colour code are the significant
figures of the value, and the third of the resistor colour code is a multiplier,
e.g. referring to the table below a resistor marked with bands: red
On occasions high tolerance resistors may use a resistor colour code with
four bands for the value. Three bands are used for the significant figures and
one for the multiplier.
Resistor Colour Code
Colour |
Band 1
1st Figure |
Band 2
2nd Figure |
Band 3
3rd Figure |
Band 4
Tolerance |
Black |
0 |
0 |
100 |
|
Brown |
1 |
1 |
101 |
1% |
Red |
2 |
2 |
102 |
2% |
Orange |
3 |
3 |
103 |
|
Yellow |
4 |
4 |
104 |
|
Green |
5 |
5 |
105 |
|
Blue |
6 |
6 |
106 |
|
Violet |
7 |
7 |
107 |
|
Grey |
8 |
8 |
108 |
|
White |
9 |
9 |
109 |
|
Gold |
|
|
|
5% |
Silver |
|
|
|
10% |
None |
|
|
|
20% |
The resistor colour code is used in virtually all leaded
resistors with power dissipation levels up to about a watt. Beyond this the
resistors are generally large enough, and use a different form of construction
allowing sufficient space for the values to be marked in figures. Nevertheless
the resistor colour code is the most widely used system for leaded resistors.
The same basic concept is also used on some capacitors.
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