This mysterious IMEI

Just like people, cell phones, smartphones, tablets and modems that use the cellular network to access the Internet have their own unique “identity document” that distinguishes them from each other. For a person, this can be an identity card, license or passport, but in the case of identifying mobile devices, this means the IMEI code.

IMEI (International Mobile Identity) is a unique digital code used to identify mobile phones, tablet smartphones and some types of satellite phones.

It can be found in the following places:

By entering the numbers on one of the many IMEI code websites. It is usually printed inside the battery compartment (next to the SIM card tray).
If the device has a non-removable battery, the numbers will be printed either on the removable SIM card or on the back cover of the device.
Alternatively, it can also be displayed on the device display when using special codes or clicking on the smartphone system menus.

The IMEI is used by the GSM network to identify the "correct" phones, so if a device is stolen it can be blocked simply by using this number. In the case of stolen or lost mobile phones, just call your cellular operator and, providing the number, ask to block the device. The code will then be placed on a "blacklist" of blocked devices that can no longer be used.

What is a phone IMEI and what is it for?

What is a phone IMEI: (from English International Mobile Equipment Identity) is a unique international code that is assigned to all mobile gadgets. It represents a 15-digit number. Have a mob. devices, as well as tablets and satellite devices.

An identifier is assigned to a gadget only by special organizations. Previously, using pirated methods, it was discovered that the number can be changed using programs on a PC. However, in some regions these manipulations are considered criminal offenses.

Now it is not considered possible to reprogram the number; it is securely sewn into the microcircuit at the manufacturing plant and can only be “opened” with special equipment.

What is it for? The number is required for mobile identification. devices on the network. If the phone simultaneously operates with several SIM cards, then a number is assigned to each. You will need this in case your gadget is stolen.

Knowing it, you can block the device if lost. Now the device is blacklisted by all network operators. And even if the SIM card is changed, attackers will not be able to use it.

You can also use Imei to determine the location of its owner. So, you can easily find a lost device.

If we talk about the structure, then imei consists of 14 digits, imei sv - of 16. Using the first numbers, you can determine the device model, as well as the country of origin. The remaining numeric values display the serial number and check number. Have SV indicates the version of the current software.

Where to find it

The numerical value can be found in different ways:

If you have any questions, please let us know Ask a Question

In the smartphone itself. Unlock your phone and enter the following numbers: *#06#. This combination is suitable for any device model and cellular operator.
Inside the gadget. Open the back cover and remove the battery. Below it you will see a numeric value.
On the device box. The data is located next to the barcode.
On the warranty card page. So, the sticker with the name is pasted in by the seller.

Find a phone by IMEI

Losing a phone is a real tragedy for a modern person. And it’s not even about the cost of the device itself, but about the loss of all data and accounts. Photos, videos, social networks, and bank cards and e-wallets are also linked to the phone.

If a smartphone falls into the hands of fraudsters, the financial and moral damage can be enormous.

Therefore, operators recommend immediately calling the support service to block the SIM card - at least to prevent criminals from paying for services and goods, or transferring money to their bank cards. A simple call to the operator will protect your funds.

A mobile operator can always find out at what point in space a cell phone is located, since they display data about which database the SIM card accesses most often. Maybe that’s why many people think that it’s enough to simply find a phone by IMEI in case of loss (loss, theft).

The difficulty is that mobile operators cannot provide such information to each client, even if he still has the box and documents for payment. They only do this for law enforcement. So, if your phone goes missing, immediately contact the police, and after a while they will have information about the location of the device, even if the SIM card is removed from it.

However, as practice shows, the process takes a lot of time and is not always successful. The police deal with this issue only if the phone is in the possession of a criminal “important” to justice.

What is IMEI SV

Imei sv is an addition to the imei code used when recording billing data. SV stands for Software version. Its main difference from having an additional 2 digits.

Components of IMEI8 SV:

TAC is a type of location code. Its length is 8 numbers.
SNR – serial number. The length of the value is 6 numbers.
SVN – software version number. 2 numbers.

The first part is used to characterize the gadget model and developer. The second determines the serial number of the device, the third is assigned by the developer for the order sequence.

SVN number=99. When flashing a gadget, it needs to be changed. The first components of imei svn must be equal to the number imei (the same numbers).

By default, imei sv 00. This means that the device is new. Then, when registering online, the code will change automatically.

Why did you start testing identification?

The testing is being carried out in connection with the development in Russia of a bill on introducing a system for monitoring phones and tablets by IMEI. Russian senators prepared the document in December 2021. He assumes that only those gadgets that have an original authorized number will be able to register in the network of telecom operators. The authors of the bill stated that registration of mobile phones by their factory code could be introduced in Russia from 2023.

Rossvyaz says that identification testing must take place before the law comes into force. However, the bill has not yet been submitted to the State Duma. One of its authors, head of the temporary commission of the Federation Council for the development of the information society, Lyudmila Bokova, explained that the document is still being finalized.

Is it possible to change IMEI

Outdated models of devices could easily be changed. This was done through a terminal program and by entering a couple of commands. Currently, manufacturers have begun to “hide” the number more carefully, so the change procedure is becoming more difficult.

The number embedded in the device itself cannot be changed using the program. However, there are still models of gadgets where you can still change them. This can be done by “hacking” the device and obtaining super user rights, as well as through the developer menu.

The change process is different for each device model. There is no universal instruction. Before the actual procedure for changing imei, be sure to clarify how legal your actions are.

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Flashing the device or installing applications from unverified sources may cause the IMEI to be reset. The abbreviation means International Mobile Equipment Identity - an international unique identifier for mobile equipment. This code is written at the software level of communication modules. If the code is erased, it is impossible to make calls through the smartphone. To restore functionality, you need to change the IMEI on Android.

The IMEI code is a unique identifier for smartphones working with GSM and UMTS modules. Consists of 15 digits. The first 8 digits mean TAC/Type Allocation Code, the rest are the serial number with a check number at the end.

The code is set at the factory during manufacture, is used to identify the device on the network, and acts as the serial number of the device. With each authorization on the network, it is transmitted over the air of mobile radio communications.

Advice! IMEI can be used by mobile radio operators and law enforcement agencies to search for stolen devices and block them at the cellular operator level.

First, let’s find out whether the smartphone detects the identifier. Go to phone mode and enter the code *#06#. The IMEI code or codes will be displayed if the device supports 2 SIM cards.

If the text “IMEI is not defined” appears in the field, it means it has been reset.

Advice! You can view the IMEI in the settings, in the “About phone” section; it is written in the warranty card, on the packaging, and also on the smartphone itself, under the battery.

I would like to warn you that in some countries changing IMEI is prohibited by law. Therefore, traveling abroad with such a gadget can cause some difficulties. Also, if you are a novice user, it is better to leave the idea of changing the IMEI, as there is a chance of inadvertently damaging the device, or turning your gadget into a brick.

Technically, you can change the ID. However, the complexity of the change depends on the device itself:

on older devices you can change it using simple programs and manipulations;
on new devices (from most well-known manufacturers), to change the IMEI you need to replace the smartphone chips (processor, controllers, flash memory, etc.), which is not possible in software.

Let's look at two ways to change the Android ID.

Calling the engineering menu is different for each gadget manufacturer. You can view yours in this table, on the Internet, or in the documentation for your device.

After entering the menu, go through the following thread:

Connectivity – CDS Information – Radio Information Phone 1

If the smartphone is designed for 2 SIM cards, then the Phone 2 section will be displayed.

In Phone 1, after the letters AT+, enter EGMR = 1.7,"your_IMEI" .

In Phone 2 (if there is one) we write EGMR = 1.10,"your_IMEI" .

Press SEND AT and reboot the device. If it doesn't work, put a space after AT+.

First, you need to root your device. Then you need to install the Mobile Uncle program (Works only with MediaTek processors). You can see your processor in the “About phone” settings. Now:

In the “Engineering Mode” tab, go to “MTK Engineering Mode”.
Follow the path “Connectivity Testing – CDS information – Phone information – Phone 1, 2”.
On the line, enter the same commands as in the section above.
When finished, press SEND AT COMMAND.

IMEISV (International Mobile Station Equipment Identity Software Version) is the code that identifies the mobile phone and the version of its software.

It consists of the following elements:

Type Approval Code (TAC) - TAC code 6 digits long
Final Assembly Code (FAC) - code identifies the place of the final production stage and consists of 2 digits
Sequence Number (SNR) - individual sequence number uniquely identifying each device among others having the same TAC and FAC, 6 digits long
Software Version Number (SVN)— identifying the software version number of the mobile device, 2 digits long

Diagram of the construction of the international mobile station identification number, including software version (IMEISV):

6 digits (TAC) + 2 digits (FAC) + 6 digits (SNR) + 2 digits (SVN) = IMEISV (16 digits)

Each IMEISV element can contain only decimal numbers.

By marking the devices, the manufacturer protects TAC, FAC and SNR against unauthorized changes. The TAC type approval code is determined by the GSMA and the final location of the FAC device is coded by the manufacturer.

Checking ID by check digit

Finding a phone is not the only thing that IMEI can help the owner of a gadget with. Using the ID, you can also find out whether the device is original or counterfeit. To do this, you need to use the Luhn algorithm:

Sum all even digits of the identifier (except the check digit).
Numbers in odd positions must be converted as follows:
Add all the odd and already converted digits (except the check digit).
Sum up the values from step 1 and step 3.
If the check digit is 0, then the resulting number is a multiple of ten.
In other cases, the control number is a number that, when added to the result from step 4, will result in the nearest round (multiple of 10) number.

Let’s take “have” 35-209900-176148-2 as an example. So, according to the Luhn algorithm:

Add even symbols: 5 + 0 + 9 + 0 + 7 + 1 + 8 =30.
Convert odd numbers: 3 = 6, 2 = 4, 9 = 9, 0 = 0, 1 = 2, 6 = 3, 4 = 8.
Add up the resulting numbers: 6 + 4 + 9 + 0 + 2 + 3 + 8 = 32.
Addition: 30 + 32 = 62.
The nearest round number is 60.
We count: 62-60 = 2.
The control number is also 2. That’s right, the product is genuine!

What is phone IMEI

IMEI is a unique number that is issued to any mobile equipment operating on mobile networks such as GSM, IDEN or WCDMA. For example, this number is received by mobile phones, satellite phones, smartphones, tablets and laptops with support for mobile Internet, 3G modems and other similar devices. The number of IMEIs received corresponds to the number of SIM cards that this device can work with. For example, if a phone supports two SIM cards, then it receives two IMEIs.

The abbreviation IMEI stands for International Mobile Equipment Identity, which can be translated into Russian as an international mobile equipment identifier. Manufacturers of phones and other mobile devices receive these identifiers from special international organizations that are authorized to issue them. For example, such identifiers are issued by BABT (British Approvals Board for Telecommunications). In the future, manufacturers distribute the received identifiers to specific phones that they produce, thus achieving the uniqueness of each IMEI.

What to do with the received IMEI

The resulting code can be used for the following tasks:

checking the device before purchasing it in person through special databases for theft;
checking the production date to ensure that you do not buy a phone from a batch with massive factory defects;
tracking the current location of the turned on device and blocking mobile communications on it;
confirmation that the phone returned and received for repair is the same device.

To summarize, we can say that finding out the IMEI on your own is quite simple - to do this, just remove the cover from the phone or look into the device settings. If this is not possible, then you can recognize it by looking at the stickers on the factory box.

What is the IMEI of a phone for?

As already mentioned, IMEI is a unique phone number, so it is convenient to use it to identify phones in the mobile operator’s network. Your mobile operator can use your IMEI to identify your phone model, as well as which communication technologies it supports. This also allows mobile operators to blacklist the phone and no longer service it.

Due to its uniqueness, IMEI can be used to track a phone even if its owner changes SIM cards. In addition, IMEI can be used by customs officers to determine the legality of the phone.

How will identification testing be carried out?

The platform for the pilot project was the Central Scientific Research Institute of Communications (TsNIIS), which manages the central IMEI database, subordinate to Rossvyaz. During testing, the synchronization of the information systems of telecom operators and the central database must be checked using several interaction protocols, according to TsNIIS.

According to Rossvyaz, cellular operators will conduct the experiment separately from each other. In particular, one of them, together with TsNIIS, has already successfully tested a technology that automatically filters out IMEIs that are prohibited from accessing the network and registers those that are allowed to register. To do this, the register of numbers in the operator’s network is synchronized with the central IMEI database every two hours.

How to find out the IMEI of a phone

After assigning an IMEI to a phone, it is recorded in several ways that duplicate each other. Any of these methods can be used to find out the IMEI of a phone.

Firstly, IMEI is written into the phone’s firmware, that is, into its software. This information can be viewed at any time using the request *#06# , which must be typed on the device keyboard. The code *#06# works equally well on both push-button phones and modern smartphones with a touch screen.

After entering this code, the IMEI that was assigned to this phone immediately appears on the screen. If several IMEIs have been assigned to the phone, then all of them will appear on the screen at once.

How to find out your IMEI on Android through the phone options menu

How to change the name on Android - all the ways to change the identifier

The first thing that comes to mind when a person is looking for how to find out his IMEI on an Android phone is the standard settings menu, and for good reason. This method is the most popular among inexperienced users. When using it you need:

Unlock or turn on your gadget.
Go to the main menu and find the “Settings” item there.
Scroll up all the main parameters and configurations.
Find the “Phone Information” section and enter it.
Find out IMEI Android and all the necessary data.

Is it possible to change IMEI

In older phone models, IMEI was changed quite simply. In particular, this could be done using a terminal program and several commands. But now everything is much more complicated, because manufacturers are increasingly recording IMEI in a special memory area that cannot be rewritten programmatically.

However, it is still possible to change the IMEI on some phones. For example, this is done through the engineering menu of the device or by obtaining ROOT rights (if it is an Android smartphone). If you need to change the IMEI on your phone, then you need to look for information specific to your device. There are simply no universal instructions for changing IMEI that would work on any device.

How to check IMEI using service code

Check iPhone by IMEI - how to find out the activation date

Every owner of any cell phone can find out their unique device identifier. On Android, as on most other operating systems, this can be done using the built-in command. To do this, go to the dialing menu (Phone application) and sequentially enter the command *#06#. Owners of push-button gadgets can immediately start typing and not have to look for an application.

Important! After typing the service command, a window will immediately open in which there is only one line containing the word “IMEI” and 14 digits. If it does not open, then you need to press the “Call” button (green handset).

You can check IMEI on Android through the service combination

Today I would like to talk to you about a seemingly simple, but at the same time interesting point... IMEI and how to prepare it correctly.

So IMEI...

As you know, this number can be viewed on a mobile terminal using the combination *#06#. The GSM core network stores the IMEI database in the EIR and requests IMEI when authorizing the device in the operator’s network. The main provisions for IMEI/SV are set out in the 3GPP TS 23.003 document. Initially, IMEI codes were intended to be used as another measure of protection against the unauthorized use of illegal mobile terminals on operator networks, but not all operators sought to use this functionality, because... for the idea to fully work with Black, White and Gray IMEI code databases, their synchronization between all operators within at least one country is necessary, and the financial benefit from this event for the operator itself is slightly less than zero...

But despite this, network elements responsible for storing and checking IMEI codes were actively used in the networks of mobile operators, for example, to track changes in the IMEI and IMSI(MSISDN) value pair, i.e. in the case when the subscriber moved the SIM card from one terminal to another, the “caring” operator immediately monitors this moment in order to send the subscriber everyone’s favorite settings for MMS, GPRS, WAP and a lot of other “necessary” information...

However, as you and I know, Ukrainian operators were not so long ago “obliged” to check IMEI codes, although the system still doesn’t work fully...

Checking the legitimacy of using a mobile term in the operator’s network, i.e. comparison of the IMEI code itself with databases on the operator’s side in the case of a request for package services is carried out during the GPRS Attach procedure - the Check IMEI Req/Res function. You can read more about this here.

IMEI

The general structure of the IMEI code is shown in the figure below:

The components are:

Type Allocation Code (TAC), 8 characters long;
Serial Number (SNR), 6 characters long;
Check Digit (CD), in case of transfer of IMEI from MS to the operator’s network, this number is replaced by 0.

Check Digit acts as a checksum and is calculated using the Luhn algorithm. The CD calculation method is described below.

IMEISV

International Mobile station Equipment Identity and Software Version Number (IMEISV) differs from the “regular” IMEI by the presence of two more digits - SVN (Software Version Number), which replace the Check Digit (CD). The general structure of IMEISV is shown in the figure below:

The components are:

Type Allocation Code (TAC), 8 characters long;
Serial Number (SNR), 6 characters long;
SVN (Software Version Number), 2 characters long.

The TAC field characterizes the model and manufacturer of the device. SNR characterizes the serial number of the ME itself. The SNR value is assigned by manufacturers in sequential order.

The value SVN=99 is reserved for future use. SVN characterizes the revision of the software installed on MS and changes when it is flashed. The TAC and SNR fields must match in both the IMEI (14 digits) and IMEISV (16 digits).

Check Digit calculation method

Below we will try to calculate the CD check number for IMEI=354190023896443. To do this, we need to perform the following operations with our IMEI code:

Double the values of numbers in even positions.
Add together the doubled numbers in even positions and odd positions, while “breaking down” the numbers in even positions into their component numbers (for example, 14 should be represented as 1 and 4).
If the final number ends in 0, then CD = 0. Otherwise, CD is equal to the number that must be added to the result obtained in step 2 to get the next whole ten.

We present the results of our calculations in the form of a table:

TAC	SNR	CD
3	5	4	1	9	2	3	8	9	6	4	4	3
x2	10	2	4	16	12	8
1+0	2	4	1+6	1+2	8
The sum of the numbers that we received in the last step and the numbers in odd positions:	3 + (1+ 0) + 4 + (2) + 9 + (0) + 0 + (4) + 3 + (1) + 6 + (9) + 1 +(2) + 4 + (8) = 57
The number to be added to the next full ten:	60 – 57 = 3

I would like to note... that usually on the box when purchasing a device, a 15-digit IMEI is indicated along with a CD at the end, but the IMEI will be transmitted to the network, in which the CD will be replaced by 0. By the way, it was this moment that made me learn more about IMEI codes , because a question arose with billing data in which the IMEI values with 0 at the end were entered...

Many forums contain descriptions of software changes to IMEI of telephones of different models, but manufacturers are constantly improving methods for storing IMEI on their devices, so with each new device, changing IMEI becomes more and more difficult.

A little helper:

EIR – Equipment Identity Register

GPRS – General Packet Radio Service

IMSI – International Mobile Subscriber Identity

ISDN – Integrated Services Digital Network

MMS – Multimedia Messaging Service

MS – Mobile Station

MSISDN – Mobile Station ISDN Number

WAP – Wireless Application Protocol

Related links (en):

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Sources used:

https://phone-insider.com/chto-takoe-imei-telefona.html
https://vr4you.net/104-international-mobile-equipment-identity.html
https://www.imei.info/faq-what-is-imeisv/
https://smartphonus.com/what-is-imei-phone-and-what-is-it-for/
https://pro-gprs.info/theory/imei.html

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What is IMEI used for?

The IMEI number identifies a specific gadget. It is transmitted every time the device connects to the mobile network.

The presence of IMEI allows you to track the movements of a mobile device and its location when it is connected to the network. This way you can search for stolen phones. The mobile operator can block phones by IMEI.

In Ukraine, the IMEI registry has been maintained for many years. In the early 2010s, they planned to use such a base to block stolen devices. In recent years, it has been proposed to use it to block devices imported without customs clearance (“gray”).

You can check the presence of IMEI in the database of the Ukrainian State Radio Frequencies Center on the IMEI CODE CHECK page. The Ministry of Internal Affairs allows you to check by IMEI whether the gadget is wanted.

Using IMEI, you can find out complete information about your mobile gadget by using the website www.imei.info.

IMEI should be hidden

The IMEI number is stored in the memory of the mobile device and it can become damaged under certain conditions. For example, a vendor may release a problematic update for a smartphone that erases the IMEI. It is also common for stolen phones to have their IMEI changed to make them untraceable. Therefore, manipulation of IMEI numbers is illegal in many countries and entails criminal liability.

It is not possible for a common person to obtain an IMEI number from GSMA and there is a need for clean IMEI numbers. Therefore, you should not publicly display your device IDs.

What is the IMEI structure?

We found out what the IMEI of a phone is. This is a combination of 15 characters. Let's consider its structure based on the classic example - 35-222200-333333-4:

TAC (35-2222): 35 is the BABT (British Telecommunications Harmonization Council) code. 2222 is the model number of your gadget in the registry).
FAC(00). There may be various digital combinations: 00 - the phone was manufactured during the period when FAC was cancelled. 04 — the manufacturing country is Vietnam. 10.70 - Finland. 19, 40 - Great Britain. 20, 78 - Germany. 30 - Korea. 67 - United States. 80 - China.
SNR (333333) — serial number of the device.
SVN (4) is a special check number.

The following versions of the identifier are also found:

35-222200-333333-44. The code is deciphered in the same way, with the exception of the last two digits (44). The latter are SVN. This indicates the number of the software that is installed on your gadget.
11-222222-333333. Identifier of the new type. It differs from those presented in that it contains an 8-character TAS (11-222222).