IMEI (International Mobile Equipment Identity)
Definition
A unique 15-digit number permanently assigned to a mobile device's hardware. Used by networks to identify and block stolen devices, and by investigators to link call records, cell tower logs, and data from multiple sources to a specific handset.
- Length
- 15 digits
- Assigned to
- The device hardware, not the SIM or subscriber
- Network use
- Identifying and blocking stolen devices
- Investigative use
- Links call records, cell tower logs, and data to one handset
Common questions
How is IMEI different from a phone's IMSI or SIM card number?+
IMEI identifies the physical handset and stays fixed even if the SIM is swapped, while IMSI identifies the subscriber's account on the SIM card. Investigators often need both, since a suspect may reuse one device across multiple SIMs or one SIM across multiple devices.
Can an IMEI be altered or spoofed?+
Yes, though it is illegal in many jurisdictions and requires specialised hardware or software to reprogram the baseband. When an examiner suspects a modified IMEI, cross-checking it against carrier records and the device's other hardware serial numbers can reveal the discrepancy.
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Explained in these topics
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