
Calculation of the VIN Check Digit
(1) Assign to each number in the VIN its actual mathematical value and assign to each letter the value specified for it in the following table:
Letter in VIN  Value assigned 
A  1 
B  2 
C  3 
D  4 
E  5 
F  6 
G  7 
H  8 
J  1 
K  2 
L  3 
M  4 
N  5 
P  7 
R  9 
S  2 
T  3 
U  4 
V  5 
W  6 
X  7 
Y  8 
Z  9 
(2) Multiply the assigned value for each character in the VIN by the position weight factor specified in the following table:
Position in VIN  Weight factor specified 
1st  8 
2d  7 
3d  6 
4th  5 
5th  4 
6th  3 
7th  2 
8th  10 
9th  N/A 
10th  9 
11th  8 
12th  7 
13th  6 
14th  5 
15th  4 
16th  3 
17th  2 
(3) Add the resulting products and divide the total by 11.
(4) The numerical remainder is the check digit. If the remainder is 10 the letter "X" shall be used to designate the check digit. The correct numeric remainder, zero through nine (09) or the letter "X", shall appear in VIN position nine (9).
(5) A sample check digit calculation is shown in the following table:
VIN positions  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17 
Sample VIN  J  H  2  R  C  3  6  0  tbd  M  M  1  0  1  5  8  1 
Assigned values  1  8  2  9  3  3  6  0  n/a  4  4  1  0  1  5  8  1 
Weight factors  8  7  6  5  4  3  2  10  n/a  9  8  7  6  5  4  3  2 
(products)  8  56  12  45  12  9  12  0  n/a  36  32  7  0  5  20  24  2 
Add products: 8 + 56 + 12 + 45 + 12 + 9 + 12 + 0 + 36 + 32 + 7 + 0 + 5 + 20 + 24 + 2 == 280 
Divide the total by 11: 280/11 = 25 5/11. The remainder is 5. 
(6) Accordingly, 5 is the check digit to be inserted in position nine (9) of the VIN:
JH2RC3605MM101581
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