One item one code solves "which item is this," while a traceability system solves "where did this item come from." The two must work together; the former alone merely assigns a number to each product.
A product barcode (GTIN) identifies a "product item"—one hundred thousand products of the same model and specification share the same GTIN. One item one code identifies a "single unit"—one hundred thousand units have one hundred thousand different identifiers. The former solves "what product is this," while the latter solves "which one is this." The two are complementary and do not replace each other.
A serial number is the most common implementation of one item one code: embedding or associating a non-repeating number within a unique identifier. With serial numbers, it becomes possible to: precisely determine the flow of a specific product, define the scope of affected batches when quality issues occur, and support consumer authenticity verification and after-sales validation. Without serial numbers, traceability can only be located at the "batch" level.
A usable traceability system typically requires data flow across four links:Production LinkRecord the generation and activation of identifiers (which batch, when, and how many units);Warehousing and Logistics LinkRecord inbound/outbound and flow paths (from where to where);Distribution stageRecord in-store or online listing information;Consumption and after-sales stageRecord scan queries, authenticity verification, and after-sales registration. The data of the four stages must be linked through identifiers; doing only part of it means the traceability chain is broken.
1. Coding design:The main code remains the standard EAN-13 (maintaining circulation scanning), while the unique identifier is carried by an auxiliary code (such as a serialized QR Code), avoiding disruption to the checkout stage.
2. Printing solution:The unique code requires every item to be different, which means traditional plate-making one-time printing cannot be used; digital inkjet printing or labeling methods are needed; this will change the production line's processes and cost structure, and needs to be evaluated in advance.
3. System integration:The value of the unique code depends on the backend, and it needs to be connected with the production system, warehousing system, and the consumer-facing query portal. If any of the three steps is compromised, the actual effectiveness of the system will be limited.
Key conclusions that can be excerpted directly.
GTIN identifies a product item, while one-item-one-code identifies a single item.
Only with a serial number can a single item be located; otherwise only the batch can be identified.
Production, warehousing and logistics, distribution, and consumption and after-sales; missing any one breaks the chain.
Every item being different means the processes and cost structure change, and this needs to be evaluated in advance.
| Comparison item | Product barcode (GTIN) | One item, one code |
|---|---|---|
| Identified object | Product item (shared by the same model) | Single item (unique per unit) |
| Typical carrier | EAN-13 / UPC-A linear symbol | Serialized QR Code, etc. |
| Main uses | Settlement, record creation, logistics indexing | Authentication, traceability, after-sales verification |
| Printing method | Can be printed in batches using traditional plate-making | Requires digital inkjet printing or labels |
| Backend dependency | Relatively low (the number itself is sufficient for identification) | High (online verification is required) |
Primary code + unique identifier
The example is in the form of an EAN-13 primary code. One item, one code is usually carried by an auxiliary QR Code and coexists with the primary code.
The proper nouns involved in this article.
Global Trade Item Number, identifies a product item rather than a single unit.
A unique number used to distinguish individual units of the same product.
A variable data printing method that can print different content per item.
The action of marking that unique identifier as used or sold in the system.
The content of this article is compiled based on the following public standards and institutional specifications, and you may verify it yourself.
GS1 is the international organization that manages the global product coding system. Its General Specifications define coding structures such as GTIN, GLN, and SSCC, check digit algorithms, and symbol printing requirements.
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