An IMEI (International Mobile Equipment Identity) is a unique number, normally 15 digits long, that identifies a specific mobile device on cellular networks. It identifies the hardware, while the SIM identifies the subscriber.
Why it matters
Carriers and authorities can use the IMEI to block a lost or stolen phone from networks, depending on local rules and shared databases. The first 8 digits are the type allocation code (TAC), identifying the make and model, followed by a serial part and a final check digit calculated with the Luhn algorithm. Dual-SIM phones have two IMEIs, one per SIM slot.
You can see yours by dialing *#06# on most phones, in the settings, or on the box and the SIM tray. Buyers of second-hand devices can check the IMEI to see whether it is reported as blocked, using the carrier's or an official check service where available.
Example
A sample structure, for illustration only:
35 612345 678901 2
TAC (model) serial check digitIf the check digit does not match the calculation for the other 14 digits, the number is not a valid IMEI.
Common mistakes
- Sharing it publicly alongside other personal details.
- Assuming a factory reset changes or removes an IMEI block.
- Buying a phone without verifying its IMEI status.
- Confusing it with the serial number or the IMSI.
- Assuming rules about changing IMEIs are the same everywhere; many countries restrict it.
Related
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