There is no standard for color codes. The chart you found seems to be using the resistor color codes, but shifted by 1 for some reason.

You're just going to have to "buzz out" the connections one-by-one using an ohmmeter or something.

Answer from Dave Tweed on Stack Exchange
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Alicat
documents.alicat.com › pinouts › DOC-PINOUT-DB9.pdf pdf
DOC-PINOUT-DB9 - REV 12, November 2023 3 ⁄ 40 TM +1 (888) 290-6060
DB9 (Male and Female) Standard Pinout · Always identify proper wiring via continuity check & color when using multi-strand cables. The calibration certificate for the device should be used as the definitive reference for custom wiring options. Note: Do not connect RS-485 to RS-232 units or cables.
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Graftek
cdn.graftek.com › system › files › 14147 › original › 785605-01.pdf pdf
DB9M/DB15M/DB25M Pigtail Cable Pinout Guide
Pigtail Cable Pinout Guide · The National Instruments DB9M, DB15M, and DB25M Pigtail cables are 9-, 15-, and 25-pin male DSUB cables for connecting a variety of devices to your National · Instruments product. The following table lists the color-coded pin assignments for ·
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The original serial connectors were 25 pins, with some/many/most of the pins used. The DB-9 RS-232 connector just takes the nine most popular pins from the DB-25 connector. In either DB-25 or DB-9 connector, which pins are actually used depends on the hardware/software implementation of the serial protocol. At minimum, for two-way serial communication you need just three pins:

  • RX (Receive) - connected to TX on the other end. Pin 2 on standard DB-9 and DB-25
  • TX (Transmit) - connected to RX on the other end . Pin 3 on standard DB-9 and DB-25
  • GND (Signal ground) - Pin 5 on standard DB-9 and pin 7 on standard DB-25

(Note that sometimes particular serial cables are wired in non-standard way, but this is very rare. Indeed, there is a number of possible serial connectors). If your serial communication is one-way then you might only use two pins: TX/RX and GND.


The particular cable you have connects the six most popular lines. Cables that connect only some of the DB-9 serial lines are widely available, though do not assume that the same six pins are connected on all DB-9 cables. Depending on your needs, the six connected pins may or may not be sufficient. If you know which pins your hardware/software needs, then you would look for a cable that has those pins actually wired. For most modern needs (if "modern" can be used to apply to serial port in 2013) six wires is sufficient.


Unfortunately, there is no standard for color coding serial lines. You might hope that signal ground is black/brown, though often it is green, or some other random color. TX/RX are often yellow and green, but again you cannot count on this. The only way to know which color is connect to what pin is to test with a multimeter.

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Assuming your connector is for RS-232 (notice that a DB9 may be used for other interfaces too) there are pins that aren't used in some cases. For instance, a cable to connect two computers doesn't need the RI (ring indicator) pin; also one of the pairs RTS/CTS or DSR/DTR may not be connected, since either one or the other is used in most transmission modes. Take a look at http://pinouts.ru/SerialPorts/Serial9_pinout.shtml

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Startech
sgcdn.startech.com › 005329 › media › sets › scnm9fmxxbk › diagram › scnm9fmxxbk_diagram.pdf pdf
GENERAL NOTES 1 1 A A B B C C D D E E F F 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1
6. MOLDING PVC BLACK IN COLOR. 4. MOLDING SCREW 4-40UNC 4*38.5MM · 5. 100% METAL SHELL OF DB9PIN CONNECTORS · 2. CONNECTOR DB9 PIN FEMALE · 3. CONNECTOR DB9 PIN MALE · SPEC: LENGTH(xx) MATING VIEW · 5 · P1 · 2 · 6 · 4 · 1 · 9 · MATING VIEW · 6 · 3 · 5 · 4 · 1 · P2 · 9 · SHIELD · 7 · 8 · 4 · 5 · 6 · 2 · 3 · P2 · 6 · SHIELD · 7 · 8 · 3 · 5 · 4 · 2 · P1 · PINOUT: GREEN ·
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Farnell
farnell.com › datasheets › 1657786.pdf pdf
www.element14.com www.farnell.com www.newark.com Page <1> V1.0 05/06/12
May 6, 2012 - Serial DB9 Data · Cable ASSEMBLIES · Specifications · 1. Molded connector end requirements: A) Inner mold using PE · B) Aluminum foil wrap to connector · C) PVC - 45P, Platinum gray · 2. Cable: [2BAWG (7/0.12) * 9C + AL/MY + DW(7/0.16)] TIN Wire · : OD = 0.78 ± 0.0.3mm · Color · : ...
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US Converters
usconverters.com › downloads › support › db9_rj45_assembeling_guide.pdf pdf
DB9 RJ45 adapters
Using the standard parts you can follow the color coded guide below. If you buy another RJ45 to DB9
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Pinout Diagrams
pinoutdiagrams.com › home › db9 pinout colour code
Db9 Pinout Colour Code: A Complete Guide
June 30, 2024 - When working with the DB9 connector, it is important to consider the different wiring options available. The pinout diagram not only provides information about the pin functions but also indicates the color code associated with each wire. The color code helps users identify specific wires quickly, ...
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Pinout Diagrams
pinoutdiagrams.com › home › db9 pinout and color code
Db9 Pinout and Color Code Guide: Everything You Need to Know
June 30, 2024 - Understanding the wiring and color codes associated with these connectors is paramount for anyone involved in electronic installations, maintenance, or troubleshooting. This article will take you on a journey into the world of DB9 connectors, unraveling the complexities and shedding light on the pinouts and color codes that govern their functionality.
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Extron
extron.com › download › files › userman › RS-232cablecard68-1353-01A.pdf pdf
Extron Electronics, USA 1230 South Lewis Street Anaheim, CA 92805 USA
Extron Electronics, USA · 1230 South Lewis Street · Anaheim, CA 92805 · 714.491.1500 · Fax 714.491.1517 · Extron Electronics, Europe · Beeldschermweg 6C · 3821 AH Amersfoort · The Netherlands · +31.33.453.4040
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Custom Cable Connection
customcableconnection.com › products › serial-cable-db9-female-blunt
DB9 RS-232 Female to Blunt - All 9 Pins - 24 AWG - Serial Breakout Cab – Custom Cable Connection
DB9 Serial Breakout CableDB9 FemaleMetal HoodFully Wired all 9 Pins Stripped and Tinned24 AWG WirePVC Jacket Color Code:1 Black2 White3 Red4 Green5 Blue6 Yellow7 Orange8 Purple9 GreyShield to Shield
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Scribd
scribd.com › document › 347010137 › DB9-to-DB25-Cable-Pinouts
DB9 to DB25 Cable Pinout Guide | PDF
DB9 to DB25 Cable Pinouts - Free download as Word Doc (.doc / .docx), PDF File (.pdf), Text File (.txt) or read online for free. This document provides a pinout diagram showing the connections between a DB9 and DB25 connector for a null modem cable. It lists the pin numbers and color codes for 8 ...
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Pinout Diagrams
pinoutdiagrams.com › home › rs232 db9 cable pinout color code
RS232 DB9 Cable Pinout Color Code Guide
June 30, 2024 - With each pin serving a specific ... this code is crucial for establishing a successful connection. This article delves deep into the labyrinth of colors and wires, shedding light on the RS232 DB9 cable’s secrets like never before. When it comes to understanding the basics of the RS232 DB9 cable pinout color code, ...
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Pinout Diagrams
pinoutdiagrams.com › home › db9 rs232 pinout color code
Db9 Rs232 Pinout Color Code: A Complete Guide
June 30, 2024 - This comprehensive guide will delve into the intricate details of the DB9 RS232 pinout, focusing specifically on the color codes associated with each pin.
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Details Pin
detailspin.com › home › rs232 db9 color code pinout
RS232 DB9 Color Code Pinout: Complete Guide and Wiring Diagram
November 22, 2025 - By grasping the functionality behind each pin and the significance of color codes, one can gain a deeper understanding of the communication process and troubleshoot potential problems efficiently. Through this article, we will dive into the world of serial port cables, unravel the connection scheme of the RS232 DB9 cable, and explore the significance of color coding.
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Details Pin
detailspin.com › home › rs232 db9 pinout color code
Complete Guide to RS232 DB9 Pinout Color Code
June 16, 2024 - While referring to this pinout color code, we gain a deeper understanding of the intricate wiring configurations used in RS232 connections – connections that have become an integral part of various industries. Exploring the color code within the RS232 DB9 pinout allows us to comprehend the ...
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Metabee
metabee.com › home › blog › d-sub
DB9 Pinout: The Secret Language of Serial Ports Decoded
September 16, 2025 - Straight-through DB9 serial cables are used to connect a DTE device to a DCE device. It links each pin directly to its corresponding pin on the other end, allowing the naturally aligned transmit and receive signals to pass through. Here is a typical wiring diagram and corresponding color code for a straight-through DB9 serial cable:
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Details Pin
detailspin.com › home › rs232 pinout db9 color code
RS232 Pinout DB9 Color Code: A Complete Guide
June 16, 2024 - Whether you are a seasoned technician or a curious beginner, this comprehensive guide to the DB9 color code will equip you with the knowledge needed to navigate RS232 connections with confidence and efficiently transmit data between devices.
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Details Pin
detailspin.com › home › rs232 db9 pinout wire colors
RS232 DB9 Pinout Wire Colors: A Comprehensive Guide
November 22, 2025 - Follow the designated color code for each wire and use consistent labeling to simplify identification and future maintenance. Perform thorough testing and verification after the wiring is complete to ensure proper signal transmission and prevent potential communication failures. By focusing on proper wiring practices and adhering to industry guidelines, you can enhance the reliability and efficiency of RS232 DB9 ...
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Campbell Scientific
campbellsci.com › p17855
17855 - Serial Cable, DB9 Pin (Male) to Pigtail
The 17855 is compatible with devices that have a DB9 socket (female) port or wiring terminals.