Cabling
RJ45 Cat5 cable colour order
Quick reference for wiring Cat5, Cat5e and Cat6 RJ45 plugs using T568A or T568B.
Orientation matters: the diagrams below show the RJ45 plug with the gold contacts facing you and the cable going away from you. Pin 1 is on the left. If you flip the plug over, the order appears reversed. Tiny plastic goblin, classic networking trap.
T568B
Most common for patch leads. Use the same order on both ends for a straight-through cable.
1White / Orange
2Orange
3White / Green
4Blue
5White / Blue
6Green
7White / Brown
8Brown
T568A
Also valid. Use this if the existing site wiring already uses T568A.
1White / Green
2Green
3White / Orange
4Blue
5White / Blue
6Orange
7White / Brown
8Brown
Which one should I use?
| Normal patch lead | Use T568B on both ends, unless the site standard says otherwise. |
|---|---|
| Existing cabling | Match whatever standard is already used. |
| Crossover cable | T568A on one end and T568B on the other. Rarely needed now because modern kit usually supports auto MDI-X. |
| Important | Do not mix standards randomly. Pick one standard and keep both ends consistent. |
Need cabling cleaned up or documented?
Alreetech can help map ports, label cabinets and turn mystery spaghetti into usable network documentation.