What Is EAN-13: A Beginner's Guide to the 13-Digit Barcode

What is EAN-13?

EAN-13 (European Article Number, now part of the GTIN family) is a 13-digit barcode standard used to identify retail products. It encodes a 13-digit numeric code into a machine-readable barcode symbol that point-of-sale (POS), inventory systems, and scanners can read to retrieve product information quickly and reliably.

Structure of an EAN-13 number

• Country or GS1 prefix (first 2–3 digits): Identifies the GS1 member organization that issued the number; it often corresponds to a country code range but does not strictly indicate where a product was made.
• Company prefix (next digits): Assigned by GS1 to a company; length varies depending on how many digits the prefix consumes.
• Item reference (next digits): Assigned by the company to identify a specific product, variant, or pack size.
• Check digit (last digit): A single-digit checksum calculated from the preceding 12 digits to validate the code.

How the check digit is calculated (simple method)

To validate or compute the 13th digit, use the following steps:

1. From the rightmost of the first 12 digits, multiply digits in odd positions by 1 and digits in even positions by 3.
2. Sum all the resulting products.
3. The check digit is the smallest number that, when added to the sum, results in a multiple of 10 (i.e., (10 - (sum mod 10)) mod 10).

Example (digits: 400638133393): compute check digit for 400638133393X

Multipliers (from right): positions alternate; sum = (4*1) + (0*3) + (0*1) + ... etc. The resulting check digit is 1, producing 4006381333931 as the full EAN-13.

Encoding in the barcode symbol

The EAN-13 barcode graphic includes guard bars at the left, center, and right that help scanners determine direction. Digits are encoded using patterns of light and dark bars; the left and right halves use different encodings so orientation is detectable. The barcode also requires a quiet zone (blank margin) around the symbol for reliable scanning.

EAN-13 vs UPC-A, EAN-8, and GTINs

• UPC-A: A 12-digit barcode widely used in the United States; UPC-A codes can be converted to EAN-13 by adding a leading 0 (zero) to create a compatible GTIN-13 in many systems.
• EAN-8: A compact 8-digit barcode used for very small packages where a full EAN-13 won’t fit.
• GTIN: The Global Trade Item Number family includes GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), and GTIN-14 and is the standard identifier many retailers and marketplaces require.

Common use cases

• Point-of-sale price lookup and sales recording.
• Inventory tracking in warehouses and retail storerooms.
• Product listings on e-commerce platforms and marketplaces.
• Inbound/outbound scanning for logistics and distribution.
• Sales analytics and demand forecasting using scanned transaction data.

Printing and scanning best practices

• Ensure adequate print contrast (dark bars on light backgrounds) and avoid patterns or colors that obscure the bars.
• Respect the minimum barcode size and quiet zone recommended by GS1; shrinking too small can make the symbol unreadable.
• Use quality barcode fonts or a verified barcode generator; always test scans with typical POS and handheld scanners.
• Place the barcode where it will not be distorted by packaging curves or seams.

How to obtain EAN-13 numbers

1. Join your local GS1 member organization to receive an official company prefix (the standard, recommended path for global recognition).
2. Assign item reference numbers under your prefix for each SKU.
3. Generate the full GTIN-13 (including check digit) and integrate it into packaging and systems.

Limitations and cautions

Buyers should avoid ambiguous or reused barcodes from third‑party resellers unless they understand the ownership and rights to use the number. Incorrect or duplicate codes cause listing rejections, checkout errors, and inventory mismatches.

For beginners, think of EAN-13 as the universal numeric identity on a retail product that ties packaging to pricing, inventory, and product data—simple to scan, but supported by an important administrative process (GS1 registration and careful SKU management).