Machine Readable Travel Documents - ICAO

Part 3. Machine Readable Official Travel Documents — Volume 1
Section IV. Technical specifications IV-15
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
15.1.7 Example 1 — Application of check digit to date field. Using 27 July 1952 as an example, with the
date in numeric form as specified in ISO 8601, the calculation will be:
Date: 5 2 0 7 2 7
Weighting: 7 3 1 7 3 1
Step 1 (multiplication) Products: 35 6 0 49 6 7
Step 2 (sum of products) 35 + 6 + 0 + 49 + 6 + 7 = 103
Step 3 (division by modulus)
103 = 10, remainder 3
10
Step 4. Check digit is the remainder, 3. The date and its check digit shall consequently be written as 5207273.
15.1.8 Example 2 — Application of check digit to document number field. Using the number AB2134 as an
example for coding a 9-character, fixed-length field (e.g. passport number), the calculation will be:
Sample data element: A B 2 1 3 4 < < <
Assigned numeric values: 10 11 2 1 3 4 0 0 0
Weighting: 7 3 1 7 3 1 7 3 1
Step 1 (multiplication) Products: 70 33 2 7 9 4 0 0 0
Step 2 (sum of products) 70 + 33 + 2 + 7 + 9 + 4 + 0 + 0 + 0 =
125
Step 3 (division by modulus) 125 = 12, remainder 5
10
Step 4. Check digit is the remainder, 5. The number and its check digit shall consequently be written as
AB2134