Free IMEI Validator
Instantly check if any 15-digit IMEI number is structurally valid using the Luhn algorithm.
Tip: Dial *#06# on your phone to instantly see your IMEI
How IMEI Validation Works
Every IMEI number contains a check digit — the 15th digit — calculated using the Luhn algorithm. This lets you verify that an IMEI is correctly formatted before running a full database check.
- Starting from the rightmost digit, double every second digit.
- If the doubled value is greater than 9, subtract 9.
- Sum all digits in the sequence.
- If the total is divisible by 10, the IMEI check digit is valid.
Note: Luhn validation only checks the format. A structurally valid IMEI does not guarantee the device is blacklist-free or unlocked.
What is a TAC Code?
The first 8 digits of an IMEI form the Type Allocation Code (TAC). The TAC identifies the device manufacturer and model, and is registered with the GSMA — the global mobile industry body. The remaining digits are the serial number and check digit.
Frequently Asked Questions
What is IMEI validation?
IMEI validation checks whether a 15-digit IMEI number is structurally correct using the Luhn algorithm. A valid IMEI passes the check digit formula, meaning the number was correctly formed, though this does not confirm the device exists or is clean.
How does the Luhn algorithm work for IMEI?
The Luhn algorithm validates the 15th digit of an IMEI. Starting from the right, every second digit is doubled. If the doubled value exceeds 9, subtract 9. Sum all digits; if the total is divisible by 10, the IMEI is valid.
Does a valid IMEI mean the phone is clean?
No. A valid IMEI only means the number format is correct. To check if a device is blacklisted, carrier locked, or has an iCloud lock, run a full IMEI check.
What is a TAC code in IMEI?
TAC stands for Type Allocation Code, the first 8 digits of an IMEI. It identifies the device manufacturer and model. The TAC is registered with the GSMA.
How do I find my IMEI number?
Dial *#06# on any phone to instantly display the IMEI. On iPhone, check Settings > General > About. On Android, check Settings > About Phone > Status.