European Article Number

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EAN-13 (GTIN-13) number encoded in EAN-13 barcode symbol. First digit is always placed outside the symbol, additionally right quiet zone indicator (>) is used to indicate Quiet Zones that are necessary for barcode scanners to work properly.
EAN-13 (GTIN-13) number encoded in EAN-13 barcode symbol. First digit is always placed outside the symbol, additionally right quiet zone indicator (>) is used to indicate Quiet Zones that are necessary for barcode scanners to work properly.

A European Article Number (EAN) is a barcoding standard which is a superset of the original 12-digit Universal Product Code (UPC) system developed in North America. The EAN-13 barcode is defined by the standards organisation GS1. It is also called a Japanese Article Number (JAN) in Japan. UPC, EAN, and JAN numbers are collectively called Global Trade Item Numbers (GTIN), though they can be expressed in different types of barcodes.

The EAN-13 barcodes are used worldwide for marking retail goods. The less commonly used EAN-8 barcodes are used also for marking retail goods; however, they are usually reserved for smaller items, for example confectionery. In EAN-13 the symbol encodes 13 numerals divided into four parts:

  • System code, the first two or three digits, usually identifying the country in which the manufacturer is registered (not necessarily where the product is actually made). When the EAN-13 barcode is a conversion of a 10-digit ISBN or ISSN code, the system code will be 978 or 979 for ISBNs (Bookland), or 977 for ISSNs.
  • Manufacturer code, consisting of four, five or six digits depending on the length of the system or country code.
  • Product code, consisting of five digits.
  • Check digit, a single checksum digit. The check digit is computed modulo 10, where the weights in the checksum calculation alternate 1 and 3. In particular, since the weights are relatively prime to 10 the EAN system will detect all single digit errors. But since the difference of consecutive weights is even, the EAN system does not detect all adjacent transposition errors.

2-digit and 5-digit supplemental barcodes may be added for a total of 14 or 17 data digits. These are generally used for periodicals (to indicate the serial number) and books (to indicate the selling price) respectively.

Contents

[edit] Country codes

Further information: List of GS1 country codes

The first three digits of the barcode of any product represents the country. Note that EAN codes beginning with 0 are rarely used, as this is just an addition to a 12-digit UPC. Since most scanners and registers worldwide can read both equally, most manufacturers in North America still only use UPC.

[edit] Encoding

Encoding EAN-13
Encoding EAN-13
the numbers of code L
the numbers of code L
the numbers of code G
the numbers of code G
the numbers of code R
the numbers of code R

To encode an EAN-13 barcode, the digits are first split into 3 groups, the first digit, the first group of 6 and the last group of 6. The first group of six is encoded using a scheme whereby each digit has two possible encodings, one of which has even parity and one of which has odd parity. The first digit is encoded by selecting a pattern of choices between these two encodings for the next six digits, according to the table below. (Unlike the other digits, the first digit is not represented directly by a pattern of bars.) All digits in the last group of six digits are encoded using a single set of patterns which are the same patterns used for UPC.

If the first digit is zero, all digits in the first group of six are encoded using the patterns used for UPC, hence a UPC barcode is also an EAN-13 barcode with the first digit set to zero.

Structure of EAN-13
First digit First group of 6 digits Last group of 6 digits
0 LLLLLL RRRRRR
1 LLGLGG RRRRRR
2 LLGGLG RRRRRR
3 LLGGGL RRRRRR
4 LGLLGG RRRRRR
5 LGGLLG RRRRRR
6 LGGGLL RRRRRR
7 LGLGLG RRRRRR
8 LGLGGL RRRRRR
9 LGGLGL RRRRRR
Encoding of the digits
Digit L-code G-code R-code
0 0001101 0100111 1110010
1 0011001 0110011 1100110
2 0010011 0011011 1101100
3 0111101 0100001 1000010
4 0100011 0011101 1011100
5 0110001 0111001 1001110
6 0101111 0000101 1010000
7 0111011 0010001 1000100
8 0110111 0001001 1001000
9 0001011 0010111 1110100

Note: Entries in the R-column are bitwise complements of the respective entries in the L-column. Entries in the G-column are the entries in the R-column reversed. See pictures of all codes against a colored background.

[edit] Checksum calculation

The checksum i calculated taking a varying weight value times the value of each number in the barcode to make a sum. The sum is then rounded up to the nearest whole ten number, if it isn't already.

[edit] Weight

The weight for a specific position in the EAN-code is either 3 or 1. An EAN18-code start with a weight of 3. All other valid EAN-codes get's their weight values for the position of the code from this table making their code line up to the right:

Weights
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
3 1 3 1 3 1 3 1 3 1 3 1 3 1 3 1 3

[edit] Calculation

Taking the numbers from an EAN 8 code we get: 7351353 or in the table:

Getting the weights for a barcode
Position 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Weight 3 1 3 1 3 1 3 1 3 1 3 1 3 1 3 1 3
Code 7 3 5 1 3 5 3
Sums 21 3 15 1 9 5 9

The sum from this barcode is then: 63
Rounding this up to it's nearest ten we get: 70
The nearest ten minus the sum makes the checksum: 70 - 63 = 7

The complete EAN 8 code is then: 73513537

[edit] See also