ISBN specifications are available from:

American National Standards Institute (ANSI) 11 West 42nd Street, 13th Fl.

New York, New York 10036 Tel. 212.642.4900 www.ansi.org

document ISO 2108:1992

The UPC/EAN checksum character

The last character in a UPC-A, UPC-E, UPC-E1, EAN-13 or EAN-8 bar code is the checksum. For reference, these are the methods of calculation:

Checksum calculation for UPC-A, EAN-13 and EAN-8

Use Worth Data’s phone number (it's not a real UPC-A code) as sample data:

18314589938

Assign even and odd positions, starting at the right and moving left:

8

3

9

9

8

5

4

1

3

8

1

odd

even

odd

even

odd

even

odd

even

odd

even

odd

1.Starting with the leading digit, 8, take the sum of all the characters in the odd positions.

8 + 9 +8 + 4 + 3 + 1 = 33

2.Multiply the result of step 1 by 3.

33 x 3 = 99

3.Now take the sum of all the even-position characters.

3 + 9 + 5 + 1 + 8 = 26

4.Add the result in Step 2 to the result in Step 3.

99 + 26 = 125

5.Subtract the result from the next higher multiple of 10.

Next higher multiple of 10 over 125 = 130

130 - 125 = 5

5 is the Modulo-10check character. The data to be printed

becomes:

183145899385.

This same formula is used for EAN-13 (using the 1-12 digits) and EAN-8 (using the 1-7 digits).

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Worth Data RF Laser user manual + 9 +8 + 4 + 3 + 1 =, 33 x 3 =, + 9 + 5 + 1 + 8 =, 99 + 26 =, 130 125 =, 183145899385