/*test3*/ ESN, IMEI/MEID and Other Annoying Words to Remember - Definitions
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IMEI/MEID, ESN and Other Annoying Words to Remember

IMEI iPhone
IMEI/MEID, ESN and Other Annoying Words to Remember

5 Ways to Find iPhone IMEI Number Correctly [Video]

Video uploaded by UnlockBoot on May 20, 2017

IMEI/MEID, ESN and Other Annoying Words to Remember

Every person has some sort of ID, either a Social Security Number or a Driver’s License. Mobile phones have their own IDs as well. Each phone gets their own ID assigned to them, when they are being made in factories. And just like humans, phones can be tracked by their identity codes.

The first thing you should know is that there are two leading mobile service provider technologies in the world. Code Division Multiple Access and Global System for Mobiles. A mobile phone can support either CDMA or GSM, but not both.

But recently the situation has changed. Most phone-makers started releasing phones that are wired for both networks form the start. Apple iPhones starting with the iPhone 6 are compatible with both networks as well as the latest Android devices. 4G/LTE is supported both in CDMA and GSM by default, 3G and 2G are supported at random. Remember to consult the vendor before buying your next device. Nevertheless, you can use one technology at a time, the phones won’t work simultaneously.

The supported technology determines an identification number. The GSM identification number is called an International Mobile Equipment Identification (IMEI) or Mobile Equipment Identifier (MEID). CDMA’s identification number is called an Electronic Serial Number (ESN).

Five of the seven largest mobile service providers in the U.S. use the CDMA technology: Verizon, Sprint, MetroPCS, Cricket and U.S. Cellular. The other two, AT&T and T-Mobile, support GSM. Foreign providers gravitate to the GSM standard as well taking up more than seventy percent of the global market.


CDMA does not use a SIM card. That’s why an ESN on a CDMA network identifies both a device and a customer. When the phone is active, it sends the ESN to the nearest base station and the provider can see it in its grid. Changing phones or activating new services means changing the ESN as well. The account should be tied to the new identifier before making any calls or sending any texts.

Since 2006, manufacturers have been running out of unique ESNs, so they are likely to be replaced with MEIDs.

IMEI / MEID Numbers

The IMEI number on a GSM network is much more comfortable to use. It identifies a particular mobile device and not the person who uses or owns it. For storing subscriber’s information, GSM uses a Subscriber Identity Module card or SIM-card for short. One can change phones, tablets and smart watches without a provider knowing about it. The only thing to do is to take the SIM-card out of the old gadget and put it into the new one.

IMEI numbers contains 15 or 17 digits and its format looks like this: AA-BBBBBB-CCCCCC-D:

  • AA: These two digits are for the Reporting Body Identifier, indicating the GSMA approved group that allocated the TAC (Type Allocation Code).
  • BBBBBB: The remainder of the TAC (FAC)
  • CCCCCC: Serial sequence of the Model (SNR)
  • D: Luhn check digit of the entire model or 0 (This is an algorithm that validates the ID number) (CD)
imei meid - IMEI/MEID, ESN and Other Annoying Words to Remember



Manufacturers agreed that it’s also useful to put down the version of the software that helps to record IMEI into the handheld. Since 2004 IMEI Software Version numbers help identify the software version running on the device.

IMEI SV’s usually contain 2 digits: 05 or 95.

If a phone features two SIM slots, each should have an IMEI and an IMEI SV.

How IMEI and ESN can help find a stolen phone

These identifiers go a long way to help find and block stolen phones. A CDMA carrier can flag the ESN as stolen and block the compromised account until further notice from the subscriber. The same trick works for defaulting subscribers who fail to pay their bill.

At first, GSM carriers could only block a compromised phone by its SIM card only. But since 2012, AT&T and T-Mobile modified their systems to block phones by IMEI as well. All seven carriers created a database of stolen IMEI numbers and ESNs. A criminal can’t use a stolen phone on a different provider’s network. This leads us to our next question: what is a bad IMEI, and a bad ESN?

A bad IMEI or a bad ESN is a blacklisted identifier. The reasons are various. The device may have been stolen; it could have belonged to a tax-dodger or a poor debtor. It’s always a good idea to check the IMEI number on www.imei.info, if you are considering buying a second hand phone or tablet. We, at iGotOffer- always makes sure to check this database before buying anyone’s device because we respect property rights.

Where Can I Find My ESN/IMEI/MEID?

These numbers can be found on phone boxes, on the back of a phone, under a battery, on a SIM tray or in the Settings and About This Phone menu. Most phone companies won’t take any chances. They will print the ID number on a box sticker, mark the SIM tray and hide it in the menu. If you like taking shortcuts you can always dial *#06# on your phone and you’ll be able to find your identifying number.

The more detailed manuals can be found on the manufacturer’s’ pages online.

imei iphone ios - IMEI/MEID, ESN and Other Annoying Words to Remember

How to find IMEI in system settings

For your Apple device,  you should consult the following page: Find the serial number or IMEI on your iPhone, iPad or iPod touch.

Android devices on the other hand, are less precise and specific. You should contact your phone company’s website to find a more accurate answer.

Security Tips

Learn what the ESN or IMEI number of your phone is and make sure to have a record of it on file somewhere. If your gadget ever gets stolen, you can report the IMEI number to your carrier as soon as possible. The person who stole your phone won’t be able to use your phone for free calls or get access to any of your personal information on your phone.

The ESN/IMEI/IMEI SV are also helpful when you’re looking for spare parts. It’s the easiest way to identify the model of your phone.

If you’re going to throw away the box your phone came in, make sure the sticker with the IMEI is non-readable. Black it with a water pen or better yet- shred the box. Try not to root your Android phone, it can make it easier to lose your IMEI number to theft. Knowing the ESN or IMEI number a criminal can clone your phone. That is basically the same thing as stealing your device- and it is in fact a virtual theft of your phone. Yes, cloning one’s phone is a criminal offense and can be punishable by up to 5 years in prison..


  • If you want to get rid of your old device, you can always sell it online to iGotOffer.com, the best place to trade in your old gadgets for top cash.
  • Everything About Apple’s Products – The complete guide to all Apple consumer electronic products, including technical specifications, identifiers and other valuable information.
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