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25 pair color code

The 25 pair color code is a color code used to identify individual conductors in a kind of electrical communication wiring known as twisted pair cables. The colors are applied to the insulation that covers each conductor. The first color is chosen from one group of five colors and the other from a second group of five colors, giving 25 combinations of two colors.

The first group of colors is, in order: 'white, red, black, yellow, violet'.

The second group of colors is, in order: 'blue, orange, green, brown, slate'.

(The color violet is more commonly called purple, but in the telecommunications industry it is always referred to as violet. Similarly, slate is a particular shade of gray.)

One of the most common uses of the codes is in Category 5 computer network wiring, as used for structured cabling for switched Ethernet installations, where only the codes for the first four pairs are used.

Sometimes each wire in a pair will have a colored stripe matching the color of its paired wire. This makes it easy to identify which pair a given wire belongs to. Otherwise, to determine which pair a wire belongs to one has to note which color codes are physically twisted together.

Pair #First wireSecond wire
1WhiteBlue
2WhiteOrange
3WhiteGreen
4WhiteBrown
5WhiteSlate
6Red Blue
7Red Orange
8Red Green
9Red Brown
10Red Slate
11Black Blue
12Black Orange
13Black Green
14Black Brown
15Black Slate
16Yellow Blue
17Yellow Orange
18Yellow Green
19Yellow Brown
20Yellow Slate
21Violet Blue
22Violet Orange
23Violet Green
24Violet Brown
25Violet Slate