Resistor color codes

11,920

 

A diagram of a resistor, with four color bands A, B, C, D from left to right A diagram of a 2.7 MΩ color-coded resistor.

To distinguish left from right there is a gap between the C and D bands.

  • band A is the first significant figure of component value (left side)
  • band B is the second significant figure (some precision resistors have a third significant figure, and thus five bands).
  • band C is the decimal multiplier
  • band D if present, indicates tolerance of value in percent (no band means 20%)

 

 

The standard color code is as follows:

Color Significant

figures

Multiplier Tolerance Temp. Coefficient (ppm/K)
Black 0 ×100 250 U
Brown 1 ×101 ±1% F 100 S
Red 2 ×102 ±2% G 50 R
Orange 3 ×103 15 P
Yellow 4 ×104 (±5%) 25 Q
Green 5 ×105 ±0.5% D 20 Z
Blue 6 ×106 ±0.25% C 10 Z
Violet 7 ×107 ±0.1% B 5 M
Gray 8 ×108 ±0.05% (±10%) A 1 K
White 9 ×109
Gold ×10-1 ±5% J
Silver ×10-2 ±10% K
None ±20% M
  1. Any temperature coefficient not assigned its own letter shall be marked “Z”, and the coefficient found in other documentation.
  2. For more information, see EN 60062.
  3. Yellow and Gray are used in high-voltage resistors to avoid metal particles in the lacquer

Resistors use preferred numbers for their specific values, which are determined by their tolerance. These values repeat for every decade of magnitude: 6.8, 68, 680, and so forth. In the E24 series the values are related by the 24th root of 10, while E12 series are related by the 12th root of 10, and E6 series by the 6th root of 10.

1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2 and 10.0

 

The tolerance of device values is arranged so that every value corresponds to a preferred number, within the required tolerance.

 

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