Calculate device identifier Luhn digits.
Initialising algorithm engine for IMEI Check Digit Calculator...
How IMEI Check Digit Calculator Works?
The IMEI Check Digit Calculator works by applying the Luhn algorithm to the first 14 digits of an International Mobile Equipment Identity (IMEI) and appending the 15th digit.
- 1Enter the 8-digit Type Allocation Code (TAC) and the 6-digit serial number.
- 2Double every second digit starting from the rightmost of the 14 digits.
- 3Subtract 9 from doubled values above 9.
- 4Add all digits to get S.
- 5Append (10 − (S mod 10)) mod 10 as the 15th digit.
IMEI Check Digit Calculator Formula
The IMEI formula is Check = (10 − (Luhn sum of 14 digits mod 10)) mod 10, as specified in 3GPP TS 23.003.
S = Σ f(dᵢ) over TAC ‖ SNR (14 digits) CD = (10 − (S mod 10)) mod 10
TACis the 8-digit Type Allocation Code.SNRis the 6-digit serial number.CDis the check digit.
1 × 2 = 2 5 × 1 = 5 7 × 2 = 14 → 14 − 9 = 5 3 × 1 = 3 2 × 2 = 4 3 × 1 = 3 0 × 2 = 0 2 × 1 = 2 4 × 2 = 8 5 × 1 = 5 1 × 2 = 2 0 × 1 = 0 9 × 2 = 18 → 18 − 9 = 9 4 × 1 = 4 S = 52 Check = 8 IMEI = 49-015420-323751-8
IMEI Check Digit Calculator Conversion Table
The IMEI conversion table lists TAC and serial combinations with their check digit.
| TAC (8 digits) | Serial (6 digits) | Check digit | IMEI (15 digits) | IMEISV form |
|---|---|---|---|---|
| 49015420 | 323751 | 8 | 490154203237518 | 4901542032375101 |
| 35209900 | 176148 | 1 | 352099001761481 | 3520990017614801 |
| 35693803 | 564380 | 9 | 356938035643809 | 3569380356438001 |
| 01326300 | 123456 | 5 | 013263001234565 | 0132630012345601 |
| 86412305 | 123456 | 0 | 864123051234560 | 8641230512345601 |
The 16-digit IMEISV replaces the check digit with a 2-digit software version number (01 here) and carries no check digit.
What is IMEI Check Digit Calculator?
An IMEI Check Digit Calculator is a tool that computes or verifies the 15th digit of a mobile device identity number. Every GSM, UMTS, LTE, and 5G device has at least 1 IMEI.
Dialling *#06# on a phone displays its IMEI. The GSM Association (GSMA) allocates TAC ranges to device makers.
What are the uses of IMEI Check Digit Calculator?
There are 4 main uses of the IMEI Check Digit Calculator, including device resale, repair intake, and blacklist checks.
- Device resale: Resellers verify IMEIs before listing used phones.
- Repair intake: Repair shops catch mistyped IMEIs on job tickets.
- Blacklist checks: Carriers validate IMEIs before checking stolen-device lists.
- Device management: IT teams validate IMEIs in mobile device inventories.