What could be simpler than a regular SIM card installed in our smartphone? Today, almost every person has at least one copy of this product. And many people might have dozens of such plastic cards lying around in their desks. It would seem that in the era of frameless smartphones, wireless chargers, sending a Tesla into Space, nothing could be simpler than a small SIM card, but in reality everything is far from so simple.
The principle of SIM cards is undeservedly considered extremely simple, although, by and large, this is a real computer, presented in such a compact form factor. Today I will try to briefly go over the modules and types of SIM cards, and perhaps you will be seriously interested in this topic.
What is a SIM card
The chip, so familiar to any person today, is a subscriber identification module (this is how the abbreviation SIM is literally translated). The history of the first “SIM cards” in the form in which we are accustomed to seeing them begins in 1991, when full-size cards first appeared.
Subscriber Identification Module - subscriber identification module.
Despite its size and, as it seems to the average person, primitiveness, this card stores a lot of information. This is both the international subscriber identifier IMSI and the phone number installed on the card, tariff plan, connected services, and other information.
SIM card device
Due to the fact that the main purpose of calling cards is to store subscriber data, many people mistakenly believe that a SIM card is a more primitive analogue of a flash drive. This is not strange, because even in its shape the SIM card is quite similar to modern microSD cards. In reality, any SIM card is a meager analogue of a computer. Each card includes:
- Microprocessor;
- Permanent memory, which is used to store information and the OS (yes, SIM cards have operating system);
- RAM.
Of course, in the context of today's size of content and hardware installed in smartphones, laptops and desktop PCs, the volume of built-in and RAM on SIM cards seem insignificant, but they are enough to store operating and file systems, subscriber information, and even user phone book. What, if all this, confirms that any SIM card is a real micro-computer? 
Current SIM card formats
In addition to the design of telephone cards, I also wanted to focus your attention on the existing formats, or standards, of SIM cards used today. You can select 5 of them:
- Mini-SIM is a standard of cards that were installed in every phone not so long ago, until they were replaced by smartphones with smaller slots. Such a card has a size of 25 by 15 by 0.76 millimeters, and today is used only in push-button and outdated phone models;
- Micro-SIM is a card that replaced the Mini version and has more compact dimensions of width and length (15 by 12 mm) while maintaining the same thickness of 0.76 mm. This map became popular with the rise of smartphones. However, today its popularity is gradually “fading away”;
- Nano-SIM is the most common SIM card format today, having more compact dimensions in width, length, and thickness (12.3 by 8.8 by 0.67 mm). Its size is slightly larger than the golden chip itself, which could always be seen on SIM cards;
- eSIM is another card option, the difference between which lies not in size, but in areas of application. The prefix “e” means “Embedded”, or “Built-in”, “Pre-installed”. Such cards are installed by default in contract models of gadgets. And, if such a need arises, removing and replacing them becomes quite problematic. However, such cards cannot be called popular on the territory of the Russian Federation;
- Multi-SIM is the latest version of cards, representing a “matryoshka”, in which the layers of the card stencil are already marked by default. Having purchased such a SIM, with a simple finger press, you can select the required card format suitable for the slot in your mobile phone.
This was a brief educational program regarding the history, formats and design of modern (and not so modern) SIM cards. I hope this information was interesting and you learned something new.
Currently on many modern gadgets You can only use a smaller version of a standard SIM card - micro sim. This is due to attempts by technology manufacturers to save internal space in the device in order to place other elements more compactly and make our phones and tablets smaller, thinner, lighter and ultimately cheaper to produce than their predecessors.
Having purchased new phone or tablet (for example, Samsung, HTC, iPhone or iPad), you may find that the standard SIM card does not fit it and in order to continue using your usual SIM card after purchasing a new device, you can cut it off. The main chip remains in place, only the size of the plastic base is reduced. It’s not difficult to make a micro sim from a regular SIM card at home; you only need sharp nail scissors, a sharpened pencil, a ruler, sandpaper (or a nail file) and a little patience.
A regular SIM card is a plastic rectangle with a chip, measuring 25x15 mm. The dimensions of the micro SIM card must be 15x12 mm. You can cut a regular SIM card to the desired size as follows:
If the SIM card after resizing is larger than necessary, this can always be corrected; if the size is significantly smaller, the SIM card will become impossible to use and you will have to change it to a new one.
If you are afraid of ruining your SIM card or are simply too lazy to tinker, you can replace the standard SIM card with a card of the required size at any Beeline office. Upon presentation of a passport, the subscriber will be issued a new SIM card, or an old SIM card will be cut to micro sim format using a device that looks like a stapler. It will take a minimum of time.
The opposite situation is also possible - using a micro SIM card in devices with standard slots. To do this, you will need a special adapter for micro SIM cards, which can be purchased at any communication store. Thus, your micro SIM card will become universal for most devices.
SIM stands for "identification module") contains a lot of important data that is necessary to connect to the signal. At the same time, it limits the phone to a specific carrier or region.
The main task of a SIM card is to save account information, which allows the user to easily and simply change without changing their account. You just need to move the SIM card to . To perform this task, the SIM card is equipped with a microprocessor with software and data with card identification keys.
In addition, SIM cards can store additional information– list of user contacts, list of phone calls, text of SMS messages. Although in modern phones such data is recorded in the memory of the phone itself, and not on the SIM card.
Mini SIM card
Few modern users have seen the “big SIM” that was used in the first cell phones and was the size of a credit card. After all, today a mini SIM card is installed almost everywhere, most often referred to simply as SIM-. It has dimensions 25x15x0.76. This standard card can store up to 250 contacts, as well as operator-related information cellular communication.
Micro SIM and Nano SIM cards
The Micro SIM card has an even smaller size - 15x12x0.76. This standard was proposed by Apple and is now used in iPhone 4, 4S and all generations of iPads. Its main difference is that a significant part of the space around the perimeter of the card was removed and only the contact chip for connecting to the phone was left. If you need a Micro SIM card instead of a SIM card, you can purchase a special adapter that allows you to use it in standard phone smaller cards. At the same time, a Mini SIM card can be easily cut and turned into a Micro SIM, since the built-in functionality of both cards is the same.
With the advent of Micro SIM, it seemed that it would be used in iPhones or iPads for a long time. But when developing the new iPhone 5 model, the developers managed to reduce the size of the card even more and create Nano SIM-map. At first glance, the size of the new generation card has not changed much (9x12), but it has become lighter and almost twice as thin. The thickness of the Nano SIM card is also 15% thinner than previous SIM cards. So cutting a regular card for Nano SIM is now very problematic.
Technologies are developing, smartphones are becoming more powerful and thinner. In pursuit of reducing the size of components, developers began to develop SIM cards that for a long time didn't change shape. Now more and more often we come across questions like: “Do Xiaomi Redmi 3s what SIM card?" and the like, so we decided to make a table for you with all the data on Xiaomi models.
What types of SIM cards are there?
At first, Mini Sim (2FF) format cards were used in mobile phones, then to reduce space, companies adopted the Micro Sim (3FF) standard, but that didn’t end there. A few years later, when free space became worth its weight in gold in smartphones, the active introduction of the Nano Sim (4FF) format began, where the size of the SIM card is limited by the size of the chip itself. We dare to assume that now this format will be used for a long time, since the next step will be a complete abandonment of physical cards.
Nowadays, many operators have switched to universal SIM cards. You can make any format out of them by “squeezing out” the desired shape. You should not throw away “frames” of unnecessary sizes, since in the future you may need to make a SIM card from a small format to a larger one.
Table of SIM cards for Xiaomi smartphones
Now the majority Xiaomi phones equipped with a combination slot for different sizes. This means that you can use two SIM cards or one SIM card and one micro SD memory card at the same time. This decision Users really liked it because freedom of choice is always welcome.
| Telephone | Scheme | SIM tray type |
|---|---|---|
| Red rice 1s | ||
| Redmi 2 | ||
| Redmi 3 (X, S, Pro) |  | micro SIM+ nano SIM/SD Card |
| Redmi 4(A Pro) | | micro SIM + nano SIM/SD Card |
| Redmi Pro | | micro SIM + nano SIM/SD Card |
| Redmi Note | ||
| Redmi Note 2 (Prime) | ||
| Redmi Note 3 | ||
| Redmi Note 3 pro (SE) | | micro SIM + nano SIM/SD Card |
| Redmi Note 4 (X) | | micro SIM + nano SIM/SD Card |
| Mi2 | ||
| Mi3 | ||
| Mi4 | ||
| Mi4c/i | ||
| Mi4s | | micro SIM + nano SIM/SD Card |
| Mi5 (S, Pro) | ||
| Mi6 | ||
| Mi Note (Pro) | | micro SIM + nano SIM/SD Card |
| Mi Note 2 | ||
| Mi Mix | ||
| Mi Max | | micro SIM + nano SIM/SD Card |
We hope you found this table useful. If you find any inaccuracies, please write in the comments.
Have you ever seen a picture when in a salon mobile communications a man buys himself new smartphone and is sincerely surprised that his old SIM card no longer fits his new phone? It is worth recognizing that now such situations are becoming less and less common, but just a couple of years ago different sizes of SIM cards for smartphones could cause confusion in every second new buyer.
Current trends are such that manufacturers are constantly striving to reduce the size of the cards used. They can be understood, because smartphones are becoming more compact and thinner every year, and allocating a lot of space inside the case for a plastic card is already too wasteful. In this article we will tell you what types of SIM cards there are, how, if necessary, you can change their size, and also draw some conclusions at the end. Happy reading.
Most likely, few of our readers remember the first standard SIM card. In terms of dimensions, this SIM card was equal to a modern one credit card and was in circulation from approximately 1991 to 1996. Today SIM card similar format It’s, of course, impossible to find anymore; moreover, there are practically no mobile devices left that meet this standard. Since the release of the first replaceable formats, the sizes of SIM cards have been revised four times and always downward. Nevertheless, modern types of SIM cards differ from each other not only in size, but also in functionality, which we will discuss below. 
Mini SIM
The first card of this format appeared in 1996 as a result of the global trend towards reducing the size of mobile devices. It doesn’t carry the word mini in its name in vain, because its dimensions were reduced several times compared to the first cards, and it really seemed incredibly tiny back then. The card measured just 25x15x0.76mm and could easily fit even the smallest phones of the period. In the eyes of the modern consumer, it is these SIM cards that have acquired the status of standard ones, and today almost no one calls them mini-SIM cards.
The mini SIM format was actively used by manufacturers for a very long period and was relevant until 2012. However, the mini-sim has not completely disappeared like its predecessor, but is still used in simple push-button phones or devices with increased protection from negative environmental factors.
Micro SIM
Micro SIM cards are a kind of evolution of the previous generation SIM cards. There were practically no functional changes, as well as changes in the chip size, but the plastic part of the card was greatly reduced, due to which the dimensions of the card were 15x12x0.76 millimeters. For the first time, cards of this format were used by Apple in its new iPhones 4. However, due to the fact that the reduced size card made it possible to greatly save space in the internal layout of the smartphone, this idea was very willingly and actively taken up by other manufacturers mobile phones. Today, micro SIM cards are the most popular and widespread.
Nano SIM
When micro SIMs first appeared on the market, it seemed that this format would last as long as the cards before it. However, the restless developers from Cupertino decided that even this size was too much. Therefore, for the next flagship iPhone 5, they used absolutely new format SIM cards and called it Nano. The Nano-SIM card is very easy to distinguish from the rest, since it is actually just the chip itself without a plastic edging. More precisely, there is still a small amount of plastic on the sides of the chip, but it is so small that it is almost invisible. In addition to changing the dimensions, the cards of the new format have also become a little thinner, which is why the use of some older SIM cards in new smartphones has become problematic. The physical dimensions of the Nano SIM are 12x9x0.646 millimeters.
Unlike previous SIM card formats, Nano format cards have not yet gained such great popularity. However, with the release of new smartphone models, slots for the smallest cards are becoming more common. Thus, it is foolish to deny that the future lies with Nano SIM.
If you buy a new SIM card at a mobile phone store, then ask them to sell you a combined card. Cards of this format They combine a standard size card and a microSIM. This way you can easily switch from regular card to microformat if you purchase a new smartphone.
Multi SIM
The sizes of phone SIM cards are not all that they can differ from each other. A striking example of this is a multi-SIM card, or, as it is also called, a “programmable” SIM card. The main difference between such cards is that they do not belong to any specific mobile operator, but can be configured to work with several numbers at once. 
In terms of dimensions, such cards are most often similar to standard-sized cards, that is, mini SIM, but smaller options can also be found. Working with multi SIM is very convenient, because it, in fact, replaces the need to have a two- or three-SIM phone or even several phones, since it can usually combine ten or more numbers at once. However, there is also a downside to the coin: to use such a card, you need to have a special programmer or every time you need to enter a new number, contact the services of specialists. In addition, such cards are not entirely within the legal framework, so if problems arise, not a single mobile operator will help you.
Thermosim card
As the name suggests, these SIM cards are designed to work in extreme environments. They are made from more technologically advanced and durable plastic, so they do not lose their functionality in conditions of extreme heat or cold, and also guarantee operation in conditions of high humidity or dust. Such cards are usually made in mini format. In fact, they should not be smaller, since the devices themselves for such conditions are created rather large. 
There is no practical sense in using such a card under normal conditions. Typically, such cards are needed by polar explorers, miners, oil workers or people in other professions whose work involves extreme cold, heat, vibration or similar working conditions.
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How to cut a SIM card
If you don’t buy yourself a new smartphone every year, then you probably could have encountered an unpleasant situation when your favorite SIM card suddenly did not fit your new phone. In such situations, consultants suggest either cutting the card or contacting your telecom operator for help. Usually there is nothing complicated about this, and we will talk about the details below. 
However, the opposite situation may arise when you need to insert an already cut SIM card into a larger slot. It would seem that the situation is hopeless, but there is no need to despair. Now you can find special adapters on sale that will help you place a small card in a slot for a different format. They are usually inexpensive and suitable for almost all types of SIM cards.
Contact your telecom operator
If your SIM card does not work, you can always contact your telecom operator and get a new one. This service It is completely free for all operators. In addition, you receive a new, fresh card with the preservation of your number and all the funds that were linked to it. The only drawback of this method is that old map All your contacts and similar information will remain. Therefore, before you go to change your SIM card, make sure to transfer all the data from it to your phone or computer. 
Despite all the advantages this method, he is not particularly popular. Most often, people go to the operator's salon only when they need to get the size of the map card, since it is difficult to obtain such a size using cutting.
Let's go to the workshop
The dimensions of a microSIM card from a miniSIM are quite easy to obtain, since they do not differ in the size of the chip, but only in the amount of plastic around it. Today, in almost every smartphone store and repair shop mobile technology There is a special stapler for cutting SIM cards. This procedure is quick and quite simple. 
Most likely, you will be offered to cut the card immediately after purchase, as soon as a format discrepancy is discovered, or you can go to the nearest repair shop if you find this problem already at home. The only disadvantage of this solution is that this procedure is still not free and in most cases they will charge you about 150 rubles. Plus, you must trust a stranger, because if you handle the stapler carelessly, the SIM card can be damaged.
Cutting the SIM card manually
If you are a confident person, then you can cut the SIM card manually using ordinary scissors. To do this, you just need to find a template, it could be another SIM card of a suitable size or a sample printed on a printer. Trimming a SIM card should be done as follows:
- Connect the cards so that their chips match each other exactly.
- Press the cards firmly with your fingers so that they do not move at all while working.
- Carefully trim the sides of the card, being careful not to cut more than necessary.
- Cut the card crosswise, being careful not to touch the chip;
- After all the steps, remove the corner and slightly round the edges - you're done.
Converting a standard size card to a micro is quite easy. There is no need to have special dexterity or skills. Most likely, you will be able to do it the first time. But getting the dimensions is much more difficult. Here, if you are not confident in your abilities, it is better to contact a specialist or change your card to a new one. 
Before cutting a SIM card manually, do not forget to backup the information from this card. There is always a risk of damaging the card chip during such an operation, but at least this way you won’t lose contact numbers that are important to you
Video instructions for cutting Micro or Nano SIM yourself
We told you what sizes of SIM cards existed and what sizes SIM cards come in today. All that remains is to consolidate your knowledge and watch the video instructions on how to cut a SIM card yourself.
Conclusions
Progress does not stand still; constant evolution occurs even in those aspects of technology that are not very noticeable. It would seem that reducing the size of SIM cards does not greatly affect our ease of using a smartphone. However, this seemingly insignificant improvement allows developers to save space inside the phone body, which means offering us more advanced cameras, faster fingerprint scanners, and so on.
Nano SIM is the smallest card possible today, but it is not the pinnacle of technological progress. If rumors are to be believed, by 2021 major smartphone manufacturers may abandon physical cards altogether and completely switch to electronic eSIMs. We will still see whether this option will be better than the traditional one, but the fact that it will be much more convenient for new buyers is obvious now.
