Uniqueness: The same product of the same specification corresponds to the same product code, and different specifications of the same product should correspond to different product codes. According to the different properties of the product, such as: weight, packaging, specifications, smell, color, shape, etc., different product codes are assigned.
Permanent: Once a product code is assigned, it is not changed and is lifetime. When this kind of product is no longer produced, its corresponding product code can only be put on hold, and cannot be reused and then assigned to other products.
Meaningless: In order to ensure that the code has sufficient capacity to meet the needs of frequent product updates, it is best to use a meaningless sequence code.
Barcode check code formula:
1. First, serialize the serial number from right to left as "1,2,3,4 ..." Starting from serial number two, add the numbers on all the even serial digits and add them, multiply the sum by 3, Add all the numbers on the odd serial number and add them up, use the calculated sum to add the numbers on the even serial number just before, and then get the sum. Subtract the single digits of the sum by 10 to get the check code.
This barcode is: 977167121601X (X is the check code).
1.1 + 6 + 2 + 7 + 1 + 7 = 24
2.24 × 3 = 72
3.0 + 1 + 1 + 6 + 7 + 9 = 24
4.72 + 24 = 96
5.10-6 = 4
So the final check code X = 4. This barcode is 94.
If the result of step 5 is 10, the comparison code is 0; that is, the case of step 4 is 0.