Monday, January 26, 2009

Decoding a GSM SIM Number

Have you ever wondered whats hidden behind the long 20 digit number printed behind every SIM card you purchase ?

Its the unique SIM identifier, which holds the Network , Country, MCC-MNC details of the SIM.

The maximum length of the visible card number is 20 characters; 19 digits are preferred, but telecommunication network operators who are already issuing Phase 1 SIM cards with an identification number length of 20 digits may retain this length.

The number is composed of the following subparts:

Issuer Identification number (max. 7 digits)
  • Major Industry Identifier (MII), 2 digits, 89 for telecommunication purposes.
  • country code, 1-3 digits, as defined by ITU-T recommendation E.164.
  • issuer identifier, variable.

Individual account identification
  • individual account identification number.
  • parity check digit.

Yes.. that narrows down the issue a bit. But how do you decode the code behind it , to plain English ?

Once again, We go to
one of our known, familiar sites !

Go to the Page, And from your left side , select "Number Analysis Tools" and Select SIM number, Or you can visit this link.

Enter the 20 Digit number printed on the back of your SIM card , and Hit the Analyse Button.
You will see the Information stored in your SIM number.

Here's an Analysis Report I got from a Sri Lankan Mobitel SIM number.