UPC 2-Digit Supplement
UPC 5-Digit Supplement
UPC-E BACKGROUND INFORMATION
EAN-8 is the EAN equivalent of UPC-E in the sense that
it provides a "short" bar code for small packages. As can be seen in the
following graphic, an EAN-8 bar code is shorter than an EAN-13 bar code,
although somewhat longer than an UPC-E bar code.
NOTE: The three bar codes above are shown only for
relative size comparison. The three bar codes do not necessarily
represent the same product, nor do they represent equivalent values.
The similarities end there, however. Unlike UPC-E in which only 6 digits
are explicitly encoded, EAN-13 explicitly encodes all eight digits; the
parity of the digits carries no particular significance. This means
that although EAN-13 is compatible with UPC-A, EAN-8 has absolutely no
compatability with UPC-E.
Another difference between UPC-E and EAN-13 is that UPC-E has a direct UPC-A
equivalence--a UPC-E bar code may be "expanded" back to UPC-A. This is not
the case with EAN-8. An EAN-8 bar code is a 2- or 3-digit number system code
followed by a 4- or 5-digit product code. The EAN-8 product codes are assigned
directly by the numbering authority. This has the advantage that any company
can request an EAN-8 code regardless of its EAN-13 manufacturer or product code.
It has the disadvantage that the EAN-8 codes must be stored in each database
as a separate product since there is no way to translate an EAN-8 code to an
EAN-8 is encoded using the three EAN-13
character sets. EAN-8 also has a check digit that is
calculated in the same
way as EAN-13. Assuming we wish to encode the 7-digit message "5512345",
we would calculate the checksum in the following manner:
The total is 15 + 5 + 3 + 2 + 9 + 4 + 15 = 53. 7 must be added to 53 to produce a number
evenly divisible by 10, thus the checksum digit is 7 and the completed bar code value is
||5 * 3
||5 * 1
||1 * 3
||2 * 1
||3 * 3
||4 * 1
||5 * 3
An EAN-8 bar code has the following physical structure:
- Left-hand guard bars, or start sentinel, encoded as 101.
- Two number system characters, encoded as left-hand odd-parity characters.
- First two message characters, encoded as left-hand odd-parity characters.
- Center guard bars, encoded as 01010.
- Last three message characters, encoded as right-hand characters.
- Check digit, encoded as right-hand character.
- Right-hand guar bars, or end sentinel, encoded as 101.
Encoding the data "55123457" (the trailing "7" is the check digit), we
obtain the following:
In order to see more clearly the construction of the bar code, the following
graphic shows the exact same bar code but each character, or section, of the
bar code is indicated by alternating colors. Above the bar code, in each
colored section, is a number from 1 to 11, which corresponds to each of the
"steps," or sections, described above. You may easily compare the 1-0
sequence of each step to the graphical representation below:
- LEFT GUARD BARS (always the same): 101.
- 1st EAN-8 NUMBER SYSTEM DIGIT . Encoding with left-hand odd parity, 0110001.
- 2nd EAN-8 NUMBER SYSTEM DIGIT . Encoded with left-hand odd parity, 0110001.
- 1st EAN-8 DATA DIGIT . Encoded with left-hand odd parity, 0011001.
- 2nd EAN-8 DATA DIGIT . Encoded with left-hand odd parity, 0010011.
- CENTAR GUARD BARS (always the same): 01010.
- 3rd EAN-8 DATA DIGIT : Encoded as right-hand character, 1000010.
- 4th EAN-8 DATA DIGIT : Encoded as right-hand character, 1011100.
- 5th EAN-8 DATA DIGIT : Encoded as right-hand character, 1001110.
- CHECK DIGIT : Encoded as right-hand character, 1000100.
- RIGHT GUARD BAR (always the same): 101.
© Copyright 2006 BarCodeIsland.com, Inc. All Rights Reserved.
Information provided "as-is" without warranty. Please see details.
Contact us for usage and copy permission.