Wire and Cable Color Codes · Free Tool
Ethernet RJ45 Color Code: T568A and T568B
Look up the RJ45 pin colours for T568A and T568B, see which pins carry data, and check straight through, crossover and PROFINET M12 wiring.
T568AT568BCrossoverPROFINET M12
CableStraight through: wire both ends to the same standard (usually T568B)
Pins used by 10/100 Mbit/s1, 2, 3 and 6
Pins used by GigabitAll 8 pins
Advertisement
T568A and T568B Pinout
| Pin | T568A | T568B | Signal |
|---|---|---|---|
| 1 | White/Green | White/Orange | TX+ (10/100), BI_DA+ |
| 2 | Green | Orange | TX− (10/100), BI_DA− |
| 3 | White/Orange | White/Green | RX+ (10/100), BI_DB+ |
| 4 | Blue | Blue | BI_DC+ (Gigabit) |
| 5 | White/Blue | White/Blue | BI_DC− (Gigabit) |
| 6 | Orange | Green | RX− (10/100), BI_DB− |
| 7 | White/Brown | White/Brown | BI_DD+ (Gigabit) |
| 8 | Brown | Brown | BI_DD− (Gigabit) |
Tip: T568A and T568B swap the green and orange pairs only. Performance is the same; just use one standard consistently.
Advertisement
Frequently Asked Questions
T568A or T568B?
Both work; T568B is more common for patch cables, T568A in some government and residential standards. Be consistent.
Which pins carry 100 Mbit/s data?
Pins 1, 2, 3 and 6.
What colours does PROFINET use?
Yellow, white, orange and blue for its two pairs.
You May Also Like
Learn more on the blog
Communication protocols in DCS systems
A practical, field focused guide on instrumentationblog.in that explains the theory behind this tool and how engineers apply it on real plants.
Read Full ArticleMore Wire and Cable Color Codes
Electrical Wire Color Codes (IEC, India, UK, US)IEC 60445, India R Y BControl Panel Wiring Color Code (IEC 60204-1 and NFPA 79)IEC 60204-1, NFPA 79Thermocouple Color Codes (IEC and ANSI)IEC 60584-3, ANSI MC96.1RTD Wire Color Code and Instrument Cable ColoursIEC 60751, Pt100 3 wireFiber Optic Color Code (TIA-598) and Jacket ColoursFibres 1 to 12, Buffer tubes
More Instrumentation Tools
2 toolsInstrument Tag DecoderDecode ISA 5.1 instrument tags and look up every identification letter.6 toolsIP, NEMA and Ex Rating DecoderDecode IP codes, NEMA enclosure types, ATEX and IECEx Ex markings and hazardous area zones.9 toolsPID Tuning ToolsPID tuning calculators, PID form converter and an online PID loop simulator.4 toolsP&ID SymbolsSearchable P&ID symbols for instruments, lines, valves and flow elements.3 toolsPipe and Flange ChartsPipe schedules, ASME B16.5 flange dimensions and pressure ratings.4 toolsThread Size ChartsNPT, BSP and metric thread sizes and a thread identifier for instrument fittings.11 toolsCommunication ProtocolsModbus address, float and CRC tools, RTU timing, RS485 rules and HART commands.17 toolsTroubleshooting GuidesInteractive fault finders for transmitters, flowmeters, valves and loops.18 toolsPractice TestsInstrumentation quizzes with instant scores and explained answers.CalculatorsCalculatorsFree engineering calculators for flow, level, pressure, temperature, valves and more.ConvertersUnit Converters76 converters, 700+ units.