EAN-13 en profundidad: el código de barras más escaneado del mundo
Complete technical reference for EAN-13: encoding tables, L/G/R parity patterns, check digit calculation, and global retail implementation.
EAN-13 Deep Dive: The World's Most Scanned Barcode
EAN-13 (European Article Number, now officially called International Article Number) is the 13-digit barcode printed on virtually every retail product worldwide. Defined by ISO/IEC 15420, it is scanned billions of times daily at checkout counters across 150+ countries.
Structure
An EAN-13 barcode encodes exactly 13 numeric digits:
- Digits 1-3: GS1 prefix (country of issuing organization)
- Digits 4-12: Company prefix + item reference
- Digit 13: Check digit (Modulo 10)
The 13 digits are divided into a left half (6 digits after the leading digit) and a right half (6 digits), separated by a center guard pattern.
Encoding System
EAN-13 uses three character sets:
- L codes (odd parity): Used in the left half
- G codes (even parity): Used in the left half
- R codes: Used in the right half
The first digit is not directly encoded as bars. Instead, it determines the pattern of L and G codes used for the left six digits. This is how EAN-13 encodes 13 digits in a symbol originally designed for 12 (UPC-A compatibility).
Symbol Structure
| Component | Modules |
|---|---|
| Left quiet zone | 11 minimum |
| Start guard (101) | 3 |
| Left data (6 digits) | 42 |
| Center guard (01010) | 5 |
| Right data (6 digits) | 42 |
| End guard (101) | 3 |
| Right quiet zone | 7 minimum |
| Total | 95 + quiet zones |
Dimensions
At 100% magnification (SC 2): - Width: 37.29mm (including quiet zones) - Height: 25.93mm - X dimension: 0.33mm
Magnification range: 80% (29.83mm) to 200% (74.58mm).
UPC-A Compatibility
UPC-A is a subset of EAN-13. Any UPC-A barcode is an EAN-13 with a leading zero. All EAN-13 scanners can read UPC-A, and since 2005, all UPC-A scanners can read EAN-13. This unification simplified global retail commerce.
Supplemental Barcodes
EAN-13 can be paired with 2-digit or 5-digit supplemental barcodes. The 5-digit supplement is used on books (ISBN) to encode the suggested price. The 2-digit supplement appears on periodicals for issue numbering.
Implementation Notes
- Always verify quiet zones are sufficient (the most common print failure)
- Use black bars on white background for maximum contrast
- Print at 300 DPI minimum for reliable scanning
- Include human-readable digits below the bars in OCR-B font