Cat5e Colour Code: Both Standards, Pin by Pin
Two standards, one cable, eight conductors. The table below settles every colour question.
Quick Answer
| Pin | T568A | T568B |
|---|---|---|
| 1 | White green | White orange |
| 2 | Green | Orange |
| 3 | White orange | White green |
| 4 | Blue | Blue |
| 5 | White blue | White blue |
| 6 | Orange | Green |
| 7 | White brown | White brown |
| 8 | Brown | Brown |
The two standards swap the orange and green pairs. Everything else is identical.
Which Standard to Use
T568B
The common convention in North America and most commercial work.
T568A
Used in some federal and residential specifications, and compatible with older two pair systems.
Consistency
The real rule is to use one standard throughout an installation.
Mixed ends
A and B at opposite ends makes a crossover, which modern ports tolerate.
Reading a Cable
- Look at the conductor order through the plug.
- Orange first is B, green first is A.
- Compare both ends to identify straight or crossover.
- Test with a wiremap tool for certainty.
- Label non standard cables.
Real-World Applications
- Terminating patch cables and wall ports.
- Identifying unknown cables.
- Repairing damaged ends.
- Teaching and certification practice.
Related Guides
For the crossover application, read crossover Ethernet wiring. For the straight through use, see straight through Ethernet cable. For the LAN wiring, start with crossover LAN cable wiring.
FAQ
Does the standard affect speed?
No. Both standards carry the same performance when consistent.
What if colours are wrong?
The wiremap fails or the link negotiates lower. Retest and re-terminate.
Can I make my own order?
Technically yes, but nothing else will work with it. Use a standard.
Why two standards?
History and regional practice. B is the default in most new work.