IMEI Validator — Free Online IMEI Checker
An IMEI (International Mobile Equipment Identity) is a unique 15-digit number assigned to every mobile device. Enter any IMEI below to instantly verify it using the Luhn (mod 10) algorithm — the same method used by mobile networks worldwide.
What is an IMEI Number?
IMEI stands for International Mobile Equipment Identity. Every mobile phone — whether a smartphone, basic phone, or mobile broadband device — is assigned a unique 15-digit IMEI number at the time of manufacture. It is defined by the GSMA (Global System for Mobile Communications Association) and standardised in 3GPP TS 23.003.
The IMEI serves as a permanent hardware identifier tied to the device itself, not the SIM card. Even if you change your SIM, the IMEI remains constant. Mobile networks use the IMEI to identify devices connecting to their infrastructure, and law enforcement agencies can request network operators to block specific IMEIs — preventing stolen phones from being used anywhere in the world.
IMEI Structure — What the Digits Mean
| Digits | Name | Meaning |
|---|---|---|
| 1–8 | TAC (Type Allocation Code) | Identifies the device model and manufacturer |
| 9–14 | Serial Number (SNR) | Unique serial within the TAC group |
| 15 | Check Digit | Luhn checksum digit for validation |
How the Luhn Algorithm Works
The Luhn algorithm (also called Mod 10) is a simple checksum formula. It is used to validate IMEI numbers, credit card numbers, and other identification strings.
- Start from the rightmost digit (the check digit) and move left.
- Double every second digit from the right (digits at odd positions from the right, 0-indexed).
- If doubling produces a number greater than 9, subtract 9 from the result.
- Sum all digits (both doubled and undoubled).
- If the total modulo 10 equals 0, the number is valid.
Example: For IMEI 352136053323139 — applying the Luhn steps produces a sum ending in 0, confirming it is a structurally valid IMEI.
Where to Find Your IMEI
- Dial *#06# on your phone — the IMEI displays automatically.
- Settings → About Phone → IMEI Information (Android) or Settings → General → About (iPhone).
- Printed on the device box and the SIM card tray.
- On older phones, remove the battery to find the IMEI on the sticker underneath.
Limitations of This Tool
- This tool only checks mathematical validity using the Luhn algorithm — it does not check against any blacklist or GSMA registry.
- A "valid" result does not confirm the phone is not stolen or that the IMEI is registered with any network.
- To check a device's theft/blacklist status, contact your network carrier or visit the GSMA Device Check.
Frequently Asked Questions
What is an IMEI number used for?
IMEIs identify mobile devices on networks. Operators can block stolen or lost devices at the network level using the IMEI, preventing them from making calls or accessing data on any carrier.
Does a valid IMEI mean the device is not stolen?
No. A valid IMEI only passes the Luhn checksum — it is mathematically correct. This does not verify whether the device is blacklisted or reported stolen. Contact your carrier or GSMA for a blacklist check.
Is my IMEI stored when I use this tool?
No. The validation is performed entirely in JavaScript inside your browser. Your IMEI is never transmitted to our servers or stored anywhere.
Where can I find my IMEI number?
Dial *#06# on your phone, or check Settings → About Phone. It's also on your device's box and the SIM tray sticker.