Wire Color Codes Reference
Searchable practical reference for IEC/NEC AC mains, DC electronics, automotive wiring and Ethernet cable colors.
โ ๏ธ Safety: Wire colors vary by country, age of installation and manufacturer. Always verify with a tester, drawing, label and local electrical code before touching or connecting wires.
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Quick group
โก AC mains wire colors
| IEC / Common AC wiring | ||
|---|---|---|
| Brown | Live / Line | L |
| Blue | Neutral | N |
| Green/Yellow | Protective earth | PE |
| NEC / Common North America | ||
| Black / Red | Hot / Line | L |
| White / Gray | Neutral | N |
| Green / Bare | Ground | G |
| Common low-voltage DC | ||
| Red | Positive | + |
| Black | Negative / 0 V | โ |
| Yellow | Signal / auxiliary | Varies |
๐ DC and electronics wiring
Red
Positive supply, VCC, +V
Black
0 V, GND, negative
Yellow
Signal, switched output or auxiliary, depending on product.
๐ Automotive notes
RedOften battery positive or permanent supply.
Black / BrownOften chassis ground or negative, but vehicle standards vary.
Yellow / Blue / GreenOften signal, lighting, ignition or accessory circuits depending on manufacturer.
Use the diagramVehicle wiring colors are not universal. Check the service manual before cutting or tapping.
๐ Ethernet T568B color order
| Pin | Color | Pair |
|---|---|---|
| 1 | White/Orange | Pair 2 |
| 2 | Orange | Pair 2 |
| 3 | White/Green | Pair 3 |
| 4 | Blue | Pair 1 |
| 5 | White/Blue | Pair 1 |
| 6 | Green | Pair 3 |
| 7 | White/Brown | Pair 4 |
| 8 | Brown | Pair 4 |
๐ Engineering Notes
Color is a clue, not proofWire colors help identification, but previous repairs, imported equipment and old installations can break the expected color rule. Always test before touching.
IEC vs NEC differenceModern IEC wiring commonly uses brown for live, blue for neutral and green/yellow for PE. North American wiring commonly uses black/red for hot, white/gray for neutral and green/bare for ground.
Panels and machines varyControl panels, PLC cabinets, automotive harnesses and OEM machines often follow manufacturer-specific standards. Use drawings and terminal labels first.
Ethernet color order mattersFor RJ45 cables, keep the same standard on both ends for straight-through cables. T568B is common, but T568A is also valid when used consistently.
Wire color code reference
This page is a quick field reference for common wire colors used in AC mains wiring, low-voltage DC wiring, automotive wiring and Ethernet cables. Color alone should never be the final proof of function.
For electrical work, verify the conductor using a suitable tester, panel drawing, cable label and local code. Older installations, imported machines and repaired circuits may not follow the expected colors.
โ Frequently Asked Questions
In many IEC-style AC systems, blue is neutral. But old wiring, imported equipment and modifications can be different, so verify before work.
In modern IEC wiring, green/yellow is normally protective earth. However, never rely on color alone in old or modified wiring. Confirm with a tester and drawing.
Commonly yes, but not guaranteed. Some equipment uses black for AC line or other functions. Always confirm DC polarity with a meter.
T568B is very common for straight-through Ethernet patch cables, while T568A is also valid. The most important rule is to use the same standard on both ends unless making a crossover cable.