The Check Digit is a function of all other digits in the IMEI. The
purpose of the Check Digit is to help guard against the possibility of
incorrect entries to the CEIR and EIR equipment.
The check digit is validated in three steps:
1.
Starting from the right,
double a digit every
two digits (e.g., 5 → 10)
2.
Sum the digits (e.g., 10 → 1+0).
Check if the sum is divisible by 10.
3.
Conversely, one can calculate
the IMEI by choosing the
check
digit that would give a sum
divisible by 10.
IMEI: 35145120840121
1. (5x2, 4x2, 1x2, 0x2, 4x2, 1x2, 1x2) = (10, 8, 2, 0, 8, 2, 2)
2. (1+0+8+2+0+8+2+2) + (3+1+5+2+8+0+2 ) = 44
3. Luhn Digit : 6
IMEI: 351451-20-840121-6
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