IMEI number structure analyzer
See what each digit of an IMEI means. Enter an IMEI, a 14-digit IMEI base or a 16-digit IMEISV, and each part is labelled and explained.
The IMEI format
3GPP TS 23.003 defines the IMEI as TAC (8) + SNR (6) + CD (1) and the IMEISV as TAC (8) + SNR (6) + SVN (2).
- TAC: identifies the device model and is allocated through the GSMA. Its first two digits are the reporting body identifier.
- SNR: a serial number unique within the TAC, assigned by the manufacturer.
- CD: the Luhn check digit. It is shown on labels and screens but not sent over the network.
- SVN: the software version number, in the IMEISV only.
Until 2004 the first eight digits were split differently: a 6-digit Type Approval Code followed by a 2-digit Final Assembly Code that identified the factory. Since then the full eight digits form the TAC.
CDMA devices use a different identifier, the MEID, which is hexadecimal. Use the MEID & ESN converter for those.
Questions
Does the IMEI show where a phone was made?
No. The first two digits identify the body that allocated the TAC, such as BABT in the UK (35) or TAF in China (86), not the factory or the country of sale. Prefix 35 is used by manufacturers worldwide.
What is the difference between IMEI and IMEISV?
Both start with the 8-digit TAC and the 6-digit serial number. The IMEI ends with a Luhn check digit (15 digits in total). The IMEISV ends with a 2-digit software version number instead (16 digits in total).
How many phones can share a TAC?
The serial number has 6 digits, so one TAC covers up to 1,000,000 devices. Manufacturers request more TACs for bigger production runs.