Barcode question answer

Where do the 13 digits in an EAN-13 product barcode come from?

For users who have a 13-digit product barcode number but do not know what each part means.

Direct answer

An EAN-13 product barcode is usually built from a company prefix, an item reference and one check digit. The company prefix is assigned under the numbering system, the item reference identifies a product item and the final check digit is calculated from the first 12 digits.

Generate EAN-13 imageRead product barcode rulesUnderstand check digits

How the 13 digits are usually understood

Part
Source
Purpose
Company prefix
Assigned to a company under the numbering system
Identifies the company in the barcode system
Item reference
Assigned by the company within its prefix capacity
Identifies a specific product item or packaging level
Check digit
Calculated from the first 12 digits
Helps validate whether the number was entered correctly

Recommended workflow

1

Confirm the number source

Do not assume any 13-digit number is a valid retail barcode.

2

Understand the company prefix

The prefix length can vary, so avoid fixed mechanical splitting.

3

Assign item references consistently

Different product specifications normally need different item references.

4

Calculate the check digit

The last digit should be calculated from the first 12 digits.

5

Generate and test the image

After the number is valid, generate the EAN-13 image and test scanning.

Common mistakes

Assuming every EAN-13 number has one fixed 3+4+5+1 split.
Treating the prefix as proof of product origin.
Using the same barcode for different product specifications.
Changing the check digit manually.

FAQ

Is EAN-13 always split as prefix + company + product + check digit?

The conceptual parts are company prefix, item reference and check digit, but the exact lengths can vary.

Who assigns the item reference?

After a company has a valid prefix, it assigns item references to product items according to uniqueness rules.

Can I choose the last digit myself?

No. The final digit is a check digit calculated from the first 12 digits.