RJ45 Wiring Diagram T568A / T568B
View the eight RJ45 conductor positions for T568A and T568B and compare straight-through and crossover wiring.
A quick field reference for checking pair order before crimping or while troubleshooting cabling.
Use the tool
Pin view: plug contacts facing you, clip away/down.
Straight-through cable: use the same standard on both ends.
Crossover cable: T568A on one end and T568B on the other. Modern Auto-MDI/MDIX equipment usually makes crossover cables unnecessary.
Use the result with confidence
Recommended workflow
- Use a non-sensitive representative input for RJ45 T568A/T568B wiring.
- Run the operation and review the result before copying or exporting it.
- Validate the output in the target application or environment before relying on it.
What to verify
- Use the same T568A or T568B standard at both ends for a normal straight-through link.
- Preserve twisted pairs up to the termination; colour order alone does not guarantee performance.
- Validate the completed link with a tester or certifier appropriate to the required category.
Questions about this tool
Can I mix T568A and T568B on the same permanent link?
Use one standard consistently at both ends for normal straight-through cabling. Mixing them creates a crossover pinout.
Does the colour order alone guarantee a good cable?
No. Pair integrity, termination quality, category components and test results determine performance.
How should I validate a terminated link?
Use a cable tester or certifier appropriate to the required category and verify wire map, length and performance.