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Guide

What is an IMEI?

The IMEI (International Mobile Equipment Identity) is a unique 15-digit number that identifies every mobile device worldwide. Think of it as your phone's fingerprint.

Updated March 2026 Β· ~5 min read

IMEI Number Structure

An IMEI consists of 15 digits split into 4 blocks:

TAC
8 digits
SNR
6 digits
CD
1 digit
  • TAC (Type Allocation Code). The first 8 digits identify the manufacturer and device model. Assigned by the GSMA.
  • SNR (Serial Number). The next 6 digits form the unique serial number of that individual device within the model.
  • CD (Check Digit). The last digit is computed using the Luhn algorithm to detect typing errors.

What is an IMEI Used For?

Theft Protection

Carriers can block a stolen device across all networks using its IMEI, via the GSMA CEIR database.

Device Identification

The TAC (first 8 digits) reveals the brand, model, and chipset of any mobile device.

Warranty & Insurance

Manufacturers and insurers use the IMEI to verify device authenticity and warranty validity.

Network Diagnostics

Telecom engineers identify UE network capabilities (CA, MIMO, VoLTE) from the TAC using tools like HiCellTek TAC Lookup.

How to Find Your IMEI

1
Dial *#06#

The universal method. Type *#06# in your phone app, the IMEI appears instantly, no call required.

2
Phone Settings

Android: Settings β†’ About Phone β†’ IMEI.
iOS: Settings β†’ General β†’ About β†’ IMEI.

3
SIM Tray or Packaging

The IMEI is engraved on the SIM tray (some models), printed on the original packaging label, and on the purchase receipt.

IMEI vs TAC: What's the Difference?

The TAC (Type Allocation Code) is the first 8 digits of the IMEI. It identifies the device model (brand + reference), while the full IMEI identifies an individual unit.

For example, all Samsung Galaxy S24 Ultra devices share the same TAC, but each unit has a unique IMEI. Learn more in our guide: What is a TAC?

IMEI Frequently Asked Questions

Is the IMEI confidential?
The IMEI is not personal data in the strict sense, but it uniquely identifies a device. Do not share it publicly, a third party could use it for a fraudulent theft report.
Can you change a phone's IMEI?
Altering an IMEI is technically possible on some chipsets, but it is illegal in most countries (UK, India, France…). The IMEI is burned into the modem's NV partition at the factory.
How do I find the IMEI if the phone is lost?
Check the original packaging (IMEI label), your Google account (Find My Device) or Apple account (iCloud), or the purchase receipt. Carriers also keep the IMEI linked to your line.
What is the difference between IMEI and MEID?
The IMEI (15 digits) is used on GSM/LTE/5G networks. The MEID (14 hex characters) was used on CDMA networks (Verizon, Sprint). Today, virtually all devices use IMEI.
Does a dual SIM phone have two IMEIs?
Yes. Each SIM slot has its own IMEI. If your smartphone is dual SIM, you will see two IMEI numbers when dialing *#06#.
Does the IMEI change if I swap the SIM card?
No. The IMEI is tied to the device, not the SIM card. Changing your SIM does not change the IMEI.
How can I check if an IMEI is blacklisted?
Use the GSMA Device Check service (paid for carriers) or free tools like our IMEI / TAC lookup. A blacklisted device has been reported stolen or lost to a carrier.

Learn More

Free Tool
IMEI / TAC Lookup

Identify brand, model, and chipset in one click.
Guide
What is a TAC?

Understand the Type Allocation Code and the GSMA database.
Comparison
IMEI vs TAC vs Serial Number

Key differences between the three mobile identifiers.
Check an IMEI Now

Enter an IMEI or TAC number to instantly identify the brand, model, and chipset of any device.

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