We were tasked this week with finding our phones’ IMSI and IMEI numbers. In researching how to find these, I came across how-to’s that mentioned several other kinds of numbers. Quora helped me clarify exactly what I was looking for:
International Mobile Subscriber Identity. This is a unique identifier that defines a subscriber in the wireless world, including the country and mobile network to which the subscriber belongs. It has the format MCC-MNC-MSIN. MCC = Mobile Country Code (e.g. 310 for USA); MNC = Mobile Network Code (e.g. 410 for AT&T), MSIN = sequential serial number. All signaling and messaging in GSM and UMTS networks uses the IMSI as the primary identifier of a subscriber.
The IMSI is one of the pieces of information stored on a SIM card.
IMEI is short for International Mobile Equipment Identity and is a unique number given to every single mobile phone, typically found behind the battery.
I have an iPhone, so I found my phone’s IMEI number by going to “Settings” then “General” then “About.”
Finding my IMSI was more complicated. Instructions I found indicated “In order to find your IMSI you must have a jailbroken and activated iPhone. Otherwise your attempts will fail,” and my iPhone is not jailbroken. I found an Apple thread that suggested I could use a SIM card reader (these do not seem easy to find but I’d be happy to know where to find one). Finally, I found instructions for displaying IMSI when you dial “* # 0 6 #” which did display a number! The same site seemed to be saying the IMSI and IMEI/MEID codes were functionally equivalent numbers for Android and iPhone, respectively, but I’m not sure if that’s right. If it is, I’m not sure what number I got to display.