What is a Code 49 Barcode?

what is code 49 barcode

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Barcodes have contributed significantly to operational efficiency, data accuracy, and productivity. 

However, as technology evolved, traditional barcodes proved to be inefficient in encoding the required data. This led to the development of advanced barcode technologies such as Code 49, which expands on the capabilities of older barcodes. 

In this article, we explore Code 49 – one of the more obscure varieties of barcode technology. Specifically, we’ll discuss Code 49’s structure, application areas, benefits and some printing and designing rules. 

By the end of our discussion, you will have a good understanding of how these codes can be used to improve processes across industries. Let’s get started!

What is a Code 49 Barcode?- A Detailed View

Code 49 Barcode

Code 49 was created by David Allais in 1987 at Intermec Corporation. This barcode was developed to overcome the problem of encoding a lot of information into a small, single barcode symbology. 

Code 49 is a flexible and continuous stacked barcode symbology (multiple rows) that combines features of UPC (Universal Product Code) and Code 39 into a single code. It uses a pattern of discrete cells and modules arranged in a rectangular grid, unlike the linear barcodes that most people are familiar with.  

The unique pattern of the Code 49 barcode allows it to encode up to 49 characters per row, which is far more than the mere 20-30 characters in most 1D barcodes. Code 49 can encode the full 128 ASCII character set, making it the first stacked variable length symbology to do so. 

While many barcode types have been created over the years, the Code 49 barcode remains one of the most powerful due to its data capacity and security features. It is commonly used in the defence sector, government, logistics, supply chain, and pharmaceutical industries, where large amounts of data must be stored in minimal space. 

Code 49 is defined in AIM-BC6-2000 – Uniform Symbology Specification.

Please note that Code 49 is a type of linear barcode symbology that uses a series of parallel bars and spaces to represent data. Code 49 is often mistaken for 2D barcode symbologies such as QR code, Data Matrix, and Aztec Code. However, the two are different.

How to Recognise a Code 49 Barcode?

Code 49 barcodes can be identified by their unique pattern of bars and spaces. Code 49 consists of a series of bar code symbols stacked on top of each other. 

Each Code 49 barcode contains 18 bars and 17 spaces per row and a one-module high separator bar to separate each row. 

The first row typically consists of a quiet zone, a start pattern, and four symbol characters that encode eight characters (with the last character being a row check character), followed by a stop pattern and a trailing quiet zone.

All Code 49 symbols must contain at least two rows and can contain up to eight rows. 

Structure of Code 49 Codes

Detailed structure of Code 49 Barcode

The structure of Code 49 barcodes are composed of two to eight rows that contain the following elements: 

  • Leading quiet zone 
  • Row start pattern
  • Four symbol characters (encoding eight ASCII characters) followed by a row check character
  • Row stop pattern
  • Trailing quiet zone

Row Start and Stop Pattern

The row start and stop patterns of Code 49 are essential features that allow the barcode to be scanned in a bidirectional manner. 

The start pattern consists of a single wide module bar followed by a one-module wide space, while the end pattern comprises four modules in width. This ensures that the beginning and end of the Code 49 symbol row are accurately identified.

Symbol Characters

Each row of a Code 49 barcode contains four individual symbol characters that encode eight ASCII code characters. Each row is composed of sixteen modules forming four bars and four spaces. 

The symbol characters are arranged in the form of alternating bars and spaces, which are 1 to 6 modules wide. 

The pattern of the symbol character always begins with a bar and ends with a space. 

Code Characters

Code 49 symbol encodes two code characters into one symbol character. Each code character has a value that ranges from 0 to 48. 

Let’s take a look at how Code Characters are represented.

Code Character Value
Code Character
Hyphen (-)
Space Symbol
Dollar sign ($)
Slash mark (/)
Plus sign (+)
Percent sign (%)
S1 (Shift 1)
S2 (Shift 2)
FNC1 (Function 1)
FNC2 (Function 2)
FNC3 (Function 3)
(Numeric Shift)

Leading & Trailing Quiet Zones

The leading and trailing quiet zones are an important element of the Code 49 barcode. 

The quiet zone is a blank space on both ends of the barcode. The purpose of the quiet zone is to provide a buffer zone to prevent any interference that could affect the barcode’s readability. This ensures that the barcode can be scanned accurately and quickly without any errors or misreadings. 

Check Digits

Code 49 barcodes contain two types of check digits: a row check digit and a symbol check digit.

The row check digit is based on the Modulo 49 algorithm, which ensures that the information in each row of the barcode is correct.

The symbol check digit is based on the Modulo 2401 algorithm, which verifies that there are no errors in the entire barcode symbol. 

Data Encodation

When encoding data into a Code 49 barcode, there are three methods available. 

  • Alphanumeric 
  • Numeric-only 
  • Full ASCII encoding 

Alphanumeric Method

In the Alphanumeric method, each code character represents a single data character or special character. The Alphanumeric method involves six non-data characters: Shift 1, Shift 2, FNC 1, FNC 2, FNC 3 and Numeric Shift. These characters signify various uses and meanings within the code character pair. 

Shift 1 and 2 are used as the first characters in a coded character pair to define full ASCII characters. FNC 1 is an Alternate Symbol Type Identifier, and FNC 2 is a Field Separator. 

Whenever the Numeric Shift appears in the code, the barcode switches between Alphanumeric and Numeric encoding.

Numeric Method

The Numeric encoding method compresses long sequences of numerical digits. It works by translating five digits into three code characters using the subset of code characters 0 through 47. 

Full ASCII Encoding

The Full ASCII Method encodes characters beyond the basic alphanumeric data character set. This encoding process involves using code character pairs, with the first character of each pair being either a Shift 1 or a Shift 2 character.

Starting Modes Of Code 49

The Code 49 barcode offers six encoding/starting modes. Still, if the user leaves the mode option blank, the barcode automatically selects the most suitable mode to support higher data density. 

The six starting modes of the Code 49 barcode are. 

  • Mode 0 – regular alphanumeric mode
  • Mode 1 – concatenated mode
  • Mode 2 – numeric mode
  • Mode 3 – group alphanumeric mode
  • Mode 4 – alphanumeric mode starting shift 1
  • Mode 5 – alphanumeric mode starting shift 2
  • Mode 6 – reserved

Mode 0 - Regular Alphanumeric Mode

Mode 0 indicates that the symbol begins with an alphanumeric encoding. 

Mode 1 - Concatenated Mode

Mode 1 indicates that the barcode begins with an alphanumeric encoding and that the barcode data need to be concatenated. 

When a Code 49 symbol starts in Mode 1, the barcode reader appends the information to a storage buffer (data not transmitted). This process continues for all successive symbols that start in Mode 1, with additional messages being added to the end of previously stored messages.

Mode 2 - Numeric Mode

Mode 2 indicates that the barcode begins with numeric encoding.

Mode 3 - Group Alphanumeric Mode

Mode 3 indicates that the barcode starts in alphanumeric encoding, and it needs to be

concatenated using a group method. 

Code 49 barcodes that start in mode 3 offer an advanced form of data concatenation using a group method. The group method allows multiple symbols to be combined into a single message, allowing the data to remain in its original order, even if it is scanned in a different sequence than intended.

Mode 4 - Alphanumeric Mode Starting Shift 1

In Mode 4, the barcodes start with alphanumeric character encoding with an implicit Shift 1 character.

Mode 5 - Alphanumeric Mode Starting Shift 2

In Mode 5, the barcodes start with alphanumeric character encoding with an implicit Shift 2 character.

Where are Code 49 Barcode Used?

The Code 49 barcode is a universal symbol used in various industries. As Code 49 is a stacked barcode symbol, it can encode large amounts of data in a relatively small space.   

The Code 49 barcode is commonly used in the aerospace industry to track parts and assemblies during production and maintenance processes. It also finds extensive application in the automotive sector, where it encodes information such as serial numbers, manufacturing dates and specifications. 

How to Get a Code 49 Barcode?

Creating Code 49 barcodes is easy and free for everyone. Since Code 49 is in the public domain, online tools and free barcode generators make it accessible for anyone to generate their own codes. 

Another alternative to generate a Code 49 barcode is to use a label design and printing software like Seagull Scintific’s BarTender Software

BarTender Software is a game-changer when it comes to barcode label printing. It is super easy to use and has some advanced features that will make barcode printing processes faster, more efficient, and more cost-effective. Refer to our guide on understanding BarTender software to learn more. 

At Triton Store, we offer the best prices on BarTender software with four editions available – Starter Edition, Professional Edition, Automation Edition and Enterprise Edition. Take advantage of this great deal to get the perfect edition for your needs today! 

Please feel free to contact us through the live chat widget or by filling out a form if you have any questions regarding what BarTender software has to offer. 

Designing Rules of Code 49 Barcodes

Good barcode and label design are essential for any business to succeed. Therefore, following certain best practices when designing barcodes and labels is important. With the right strategies in place, businesses can maximise the effectiveness of their barcodes and labels while avoiding costly mistakes.

When designing Code 49 barcodes, the X-dimension, barcode width, quiet zones and barcode height are the primary considerations to keep in mind. Let us take a deep look into each design factor. 

X-Dimension of Code 49 Barcodes

The X Dimension of Code 49 is a crucial parameter that determines the barcode’s quality when scanned or printed. 

The X Dimension is the width of the narrowest bars and spaces in a Barcode. 

To ensure the optimal quality of Code 49 barcodes, the minimum X-Dimension should not be lower than 0.0075 inches (0.191 mm). This is currently the limit that reflects the technology of many standard scanning devices. 

Point on design rule of X-dimension in Code 49 Barcode
Two points on design rule of quiet zones in Code 49 Barcode

Quiet Zones

Quiet zones are areas of blank space that appear before and after a Code 49 barcode. 

The area before the barcode, the leading quiet zone, should be at least ten times wider than the narrowest bars and spaces in the code. On the other hand, the area after the barcode, referred to as the trailing quiet zone, should have a minimum width of 1X of the narrowest bars and spaces present in the code.   

Barcode Height

Barcode height refers to the total height of the barcode symbology, excluding human-readable interpretations. For Code 49 barcodes, it is recommended to have a minimum bar height of 8 times the X dimension.

Design rule of barcode height of Code 49 Barcode
Point on design rule of barcode width in Code 49 Barcode

Barcode Width

A Code 49 barcode width should be exactly 81 times the X dimension. This barcode width measurement includes a minimum of 10X for the leading quiet zone, 70X for the bars and spaces, and 1X for the trailing quiet zone.

Best Practices for Printing Code 49 Barcodes

List of four points on printing rules of Code 49 Barcode

In order to ensure the successful scanning of a Code 49 barcode, there are several printing rules that you should follow.

  • Code 49 barcodes must be printed in pure black with a white background. If colour is needed, it should be a very dark font on a very light background.
  • There should be a clear white “quiet zone” around the barcode to avoid interference and improve readability when scanning.
  • Printer settings should be set to the highest image quality for the best results and reliability. You can also adjust print resolution and print speed and experiment to find the right settings to produce scannable barcodes consistently. 
  • Testing barcodes in direct sunlight or overhead light is beneficial to ensure that all codes are detected correctly.
  • Finally, inspecting for stains, scratches, or other defects can help prevent potential problems caused by the legibility and legibility of Code 49 barcodes. 

Thermal printers are a great choice for printing Code 49 barcodes. These printing devices don’t require ink or toner, resulting in cost savings. They also have faster output speeds, which can increase productivity. Additionally, they have lower maintenance requirements, ensuring more long-term cost savings. 

At Triton Store, we provide a wide range of thermal printers from reputable manufacturers like Honeywell, Zebra, and TSC. We have direct thermal printers, thermal transfer printers, barcode label printers, desktop printers, and industrial printers that provide superior performance for any barcode and label printing application. 

Additionally, we stock print consumables of the best quality for long-lasting adhesion and print quality. Our consumables range includes thermal transfer ribbons, thermal labels, thermal carton labels, thermal carcase tags, and food-compliant thermal inserts, each of which meets the highest quality standards.


Code 49 is a versatile symbol that has been and continues to be used widely in the manufacturing industry. Its ability to store a large amount of data in a small area, combined with its extended capabilities offered through various levels of security, makes it an attractive choice for many companies looking to streamline their data storage process. 

We hope this article provided you with in-depth knowledge about Code 49 barcodes. 

Thanks for reading! 

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