Resistor Color Code Guide

Color 1st Band 2nd Band Multiplier Tolerance
Black 0 0 1 Ohm -
Brown 1 1 10 Ohm -
Red 2 2 0.1 KOhm -
Orange 3 3 1 KOhm -
Yellow 4 4 10 KOhm -
Green 5 5 100 KOhm -
Blue 6 6 1 MOhm -
Purple 7 7 - -
Grey 8 8 - -
White 9 9 - -
Gold - - 0.1 Ohm +/-5%
Silver - - - +/-10%


Here is an example of a "Green,Blue,Red, Gold" resistor:
5k6 resistor
The value is: 56 * 0.1 KOhm = 5.6 KOhm = 5K6

The E12 series

Standard resistors with 10% or 5% tolerance come in values known as E12 series. Those are the most commonly used resistors. Possible digit combinations for values in this series are:

10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82

It is called E12 because every value is approximately: previousVal * 10^(1/12) = previousVal * 1.2115

 

 

The E24, E96 series

Resistors with 5% or 2% tolerance are available according to the E24 series:
The values are approximately: newVal = previousVal * 10^(1/24) = previousVal * 1.100

10, 11, 12, 13, 15, 16, 18, 20, 22, 24, 27, 30, 33, 36, 39, 43, 47, 51, 56, 62, 68, 75, 82, 91


Resistors with 1% tolerance are available according to the E96 series:
The values are approximately: newVal = previousVal * 10^(1/96) = previousVal * 1.024275

100, 102, 105, 107, 110, 113, 115, 118, 121, 124, 127, 130, 133, 137, 140, 143, 147, 150, 154, 158, 162, 165, 169, 174, 178, 182, 187, 191, 196, 200, 205, 210, 215, 221, 226, 232, 237, 243, 249, 255, 261, 267, 274, 280, 287, 294, 301, 309, 316, 324, 332, 340, 348, 357, 365, 374, 383, 392, 402, 412, 422, 432, 442, 453, 464, 475, 487, 499, 511, 523, 536, 549, 562, 576, 590, 604, 619, 634, 649, 665, 681, 698, 715, 732, 750, 768, 787, 806, 825, 845, 866, 887, 909, 931, 953, 976


There is also an E48 series but it is not so commonly used. Resistors with tolerances lower than 5% have one color ring more and the tolerance ring is red for 2% or brown for 1%. As red and brown are also used for value encoding it is often not obvious from which side one has to read the color code. The ambiguity can be resolved by using an ohm meter.

 

 

Capacitor Code Guide

Some of the smaller capacitors (e.g ceramic capacitors) use number codes with 3 digits. The third digit denotes here the number of zeros you must add. The unit is pico-Farad (pF).

Value = digit1 digit2 * 10^ digit3 pF

Common digit3 multipliers:
5 = 0.1 μF = 100 nF
4 = 10 nF
3 = 1 nF
2 = 0.1 nF
1 = 10 pF
 Example values:
475= 4.7μF
474= 0.47μF = 470 nF
473= 0.047μF = 47 nF
472= 4.7 nF = 4700pF
471= 0.47 nF = 470pF
470= 0.047 nF = 47pF


Example capacitor "223":
22nF capacitor
The value is: 22 * 10^3pF = 22 * 1000pF = 22 000pF = 22 * 1 nF = 22 nF
© Guido Socher,