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Anatomy of the GS1-128 Barcode
Let’s geek out and dissect the GS1-128 barcode and show its inner beauty.
]C001006141419999961710010110123ABC211234567890
No FNC1 1st character
Not GS1 Symbology / Code 128
]C101006141419999961710010110123ABC211234567890
FNC1 1st character
GS1 Symbology / GS1-128
Barcode Symbology Identifier for the GS1-128
Symbology Identifiers are 3 characters codes that appear at the
beginning of a data string that tells what “kind” of barcode it is.
ISO has set aside FNC1 in the first character position as an
indicator of GS1 data (AIs and Group Separators)
Symbology Identifier Format:
]cm
] – (ASCII 93 Character) the ID flag
c- code (symbology) character
m – modifier character
*Scanners are usually defaulted to “Symbology Identifier Off”
Therefore, you need to “turn it on” to see the IDs.
GS1-128 Barcode Symbology: ]C1
GS1 Application Identifiers (AIs) for the GS1-128
GS1 Application Identifiers (AIs) are numeric prefixes used in barcodes to define the meaning and format of encoded data elements.
Here are the most common AIs used in Foodservice:
(01)
AI (01) is a fixed length numeric identifier of 14 digits, used to encode the GTIN.
The Global Trade Item Number® (GTIN®) is the globally unique GS1 Identification Key used to identify trade items. GTINs are assigned by the brand owner of the product, and are used to identify products as they move through the global supply chain
(Fill in zeros are prefixed for any of the following: GTIN-8, GTIN-12 or GTIN-13)
(3202)
AI (3202) is a fixed length numeric identifier of 6 digits, used to encode the Net Weight in pounds.
The GS1 Application Identifiers (digits A1 to A4 – see figure below) indicate that the GS1 Application Identifier data field contains the quantity or dimension of a variable measure trade item. It also denotes the unit of measure. These element strings are used to complete the identification of a variable measure trade item.
They contain information such as the weight, size, volume, or dimension of a variable measure trade item and, therefore, should never be applied alone. Several element strings are possible if the variables required are dimensions or weights expressed in kilograms and pounds.
The GS1 Application Identifier digit A4 indicates the implied decimal point position, where, for example, the digit 0 means that there is no decimal point, and the digit 1 means that the decimal point is between N5 and N6. The “applicable value” field contains the variable measure that applies to the respective trade item.
(11)
AI (11) is a fixed length numeric identifier of 6 digits, used to encode the Production Date.
The production date is the production or assembly date determined by the manufacturer. The date may refer to the trade item itself or to items contained.
(13)
AI (13) is a fixed length numeric identifier of 6 digits, used to encode the Packaging Date.
The packaging date is the date when the goods were packed as determined by the packager. The date may refer to the trade item itself or to items contained.
(15)
AI (15) is a fixed length numeric identifier of 6 digits, used to encode the Best Before or Best By Date.
Best before date on the label or package signifies the end of the period under which the product will retain specific quality attributes or claims even though the product may continue to retain positive quality attributes after this date. Best before date is primarily used for consumer information and may be a regulatory requirement.
(17)
AI (17) is a fixed length numeric identifier of 6 digits, used to encode the Use By or Expiration Date
The expiration date is the date that determines the limit of consumption or use of a product/coupon. Its meaning is determined based on the trade item context (e.g., for food, the date will indicate the possibility of a direct health risk resulting from use of the product after the date, for pharmaceutical products, it will indicate the possibility of an indirect health risk resulting from the ineffectiveness of the product after the date). It is often referred to as "use by date" or "maximum durability date.”
(10)
AI (10) is a variable length alphanumeric identifier, used to encode Batch or lot number. It is best practice to place variable length AIs at the end of a barcode string. If you have more than one variable length AI, you need to use an FNC1 character to separate the two.
The batch or lot number associates an item with information the manufacturer considers relevant for traceability of the trade item to which the element string is applied. The data may refer to the trade item itself or to items contained. The number may be, for example, a production lot number, a shift number, a machine number, a time, or an internal production code. In cases where the same product is manufactured in different locations the brand owner and the manufacturer are responsible for ensuring the non-duplication of batch/lot numbers for a GTIN. For the re-use of batch/lot numbers with a GTIN, sector-specific constraints need to be considered.
(21)
AI (21) is a variable length alphanumeric identifier, used to encode a serial number. It is best practice to place variable length AIs at the end of a barcode string. If you have more than one variable length AI, you need to use an FNC1 character to separate the two.
A serial number is assigned to an entity for its lifetime. When combined with a GTIN, a serial number uniquely identifies an individual item. The serial number field is alphanumeric and may include all characters contained in figure 7.11-1. The brand owner and the manufacturer are responsible for ensuring the non-duplication of serial numbers for a GTIN. For the re-use of serial numbers with a GTIN, sector-specific constraints need to be considered.
HRI and Non-HRI text for the GS1-128
Human Readable Interpretation (HRI) Text
Human readable interpretation (HRI) text is the text below, beside or above a barcode or tag which is encoded in the barcode or tag and represents the same characters as carried in the barcode or tag
Non-Human Readable Interpretation (HRI) Text
Non-HRI text is all other text on package, label or item
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