Sim cards micro: Standard, Micro and Nano explained

Standard, Micro and Nano explained

By James Rogerson

29th June 2022

All phones need SIM cards, but they don’t all need SIM cards of the same size. In fact, there are three different sizes in use, namely Standard, Micro and Nano. On top of that, there are also eSIMs, which are a slightly different technology.

We’ve created this guide to help you tell between them and know which one you’ll need. Plus, you’ll find some advice for what to do if you end up with a SIM card that’s the wrong size for your phone.

What is a Standard SIM card?

A Standard SIM card is, despite the name, not the most common or ‘standard’ SIM card you’ll find. But it was when it launched – hence the name.

The name also reflects the fact that this is the largest type of SIM card available at 15 x 25mm. You could think of it as a full-size card while the other two sizes are cut down.

However the chip is the same size in all three. This is the important bit that stores your data, so with a Standard SIM card you just have a lot of plastic around it.

The Standard SIM card is the oldest of them (introduced way back in 1996) and so while it was once used in many handsets, including big-name ones like the iPhone 3GS, it’s rarely used in phones now – some feature phones and very basic mobile phones still use these, as do some old handsets, but smartphones made in the last eight or nine years almost certainly won’t.

What is a Micro SIM card?

A Micro SIM card is one size down from a Standard card. So it’s a little smaller, coming in at 12 x 15mm. As noted above the actual chip is the same size, so it’s just the bit around it that’s smaller.

Having been introduced back in 2003, this card also isn’t widely in use anymore, with most handsets having moved on to newer Nano SIM cards, discussed below.

If your phone is a good few years old, but too new for a Standard SIM card, then it might use a Micro SIM, but handsets made in the last six or seven years generally don’t. As an example, the Samsung Galaxy S5 launched in 2014 uses a Micro SIM, but the following year’s Galaxy S6 uses a Nano one.

What is a Nano SIM card?

Nano SIM cards are the smallest of the bunch, coming in at 8.8 x 12.3mm, they’re also the newest, having made their debut in 2012. This has almost no border around the chip so it’s hard to imagine SIM cards getting much smaller in future, unless the chip itself is shrunk.

Nano SIM cards are by far the most widely used, so if you’re buying a new phone, it’s almost certainly one of these that you’ll need.

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What is an eSIM?

An eSIM is an embedded SIM, and this – rather than ever smaller sizes of cards – is likely to be the future of the tech.

As the name suggests, an eSIM would be built into your phone, so you wouldn’t be able to remove it. This essentially makes it smaller than even a Nano SIM card, since it doesn’t need a tray, or a slot built around it.

Beyond taking up less space there are other advantages to an eSIM. If you change network, the switch can be instant, with no need to get a new SIM card and put it in your phone. And an eSIM can house more than one network and number on it.

If you have a fairly recent high-end phone, then it might already have an eSIM. Most iPhones from the iPhone XS onwards have one for example, as do many Samsung and Google phones, among some others. But in the vast majority of cases you also get a slot for Nano SIM. So there’s no need to use the eSIM – and you might not even know it’s there.

In future though eSIMs could become more common and could start being the only option – though first more networks will need to support them, as currently only a handful do.

For more information, check out our guide covering ‘What is an eSIM and which networks/phones support eSIMs?’


Why have SIM cards shrunk?

SIM cards have shrunk primarily because the bits that were removed were essentially wasted space and space comes at a premium in a smartphone. By having a smaller SIM card slot, more space can be freed up for a larger battery or other components, or the phone can be marginally shrunk down.

Are there any other differences between SIM cards other than their size?

Generally no, in the case of Standard, Micro and Nano SIMs it’s typically just the size that they come in and therefore what phones they fit in. However, on rare occasions you will need a new SIM card to access 5G (though this isn’t necessary on most networks). eSIMs are also a bit different, as – aside from anything else – they’re not removable.

What is the evolution of SIM Cards?

We’re unlikely to get significantly smaller SIM cards in future, as noted above to get much smaller there would need to be a change to the chip itself, since Nano SIM cards already have hardly anything around the chip.

What we will probably start to see more of though is eSIMs. As explained above, these are embedded SIM cards, which is to say you won’t have a physical card that you need to put in a phone, it will be built in instead. As well as potentially being smaller there are other advantages to these, such as being able to change network without changing SIM card.

A small but growing number of phones already have one of these, but it’s primarily just Apple, Samsung, and Google phones, such as the iPhone 13 range, the iPhone 12 range, the iPhone 11 range, the iPhone XS range, the Pixel 6 range, the Pixel 5, the Pixel 4 range, the Pixel 3 range, the Samsung Galaxy S22 range, the Galaxy S21 range, the Galaxy S20 range, and Samsung’s foldable phones. However, all of these also have a normal SIM card slot, as not all networks support eSIMs yet.

What SIM card size do networks send?

Although a Nano SIM is by far the most widely used by modern handsets, most networks will actually send a Multi SIM, Combi SIM or Trio SIM, which are all different ways of saying multiple SIM card sizes in one.

In most cases that means getting all three SIM card sizes, with perforations for each size so you can easily get it to the size you need. In other words, you shouldn’t need to ask for a specific size or even know what size card you need in advance of ordering one.

What can I do if I have the wrong size SIM card?

If you get a new phone that needs a different size SIM card or end up with the wrong size for any other reason, your best option is to contact your network and ask them to send a replacement. As noted above, you’ll usually get three sizes in one, so probably won’t even have to request a specific size.

If you can’t wait for that then there are other options. If your SIM card is too small for your phone, then you could buy an adaptor. These are small pieces of plastic shaped like a Micro or Standard SIM with space for a Micro or Nano SIM inside, so you just stick your SIM card in the adaptor and then put that in your phone.

If your SIM card is too big, then you can get SIM card cutting tools which help you cut it down to the right size. However, you risk damaging it by doing this, so we wouldn’t recommend it.

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James Rogerson

Editorial Manager

James has been writing for us for over 10 years. Currently, he is Editorial Manager for our group of companies (, and and sub-editor at TechRadar. He specialises in smartphones, mobile networks/ technology, tablets, and wearables.

In the past, James has also written for T3, Digital Camera World, Clarity Media, Smart TV Radar, and others, with work on the web, in print and on TV. He has a film studies degree from the University of Kent, Canterbury, and has over a decade’s worth of professional writing experience.

View more posts by James Rogerson >

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Nano SIM, Micro SIM, or Standard SIM?

All smartphones (and feature phones and other types of mobile phones) require a SIM card to connect to a mobile network – as, in fact, do mobile broadband devices, and any tablets that offer mobile connectivity.

But while you’re sure to have at least one gadget in your life that needs a SIM card, not all SIM cards are the same, as they come in three different sizes and four different common types.

Below then we’ll explain what those three different sizes are, which you’re most likely to need, how to adapt a SIM card to a different size, whether you need a new SIM card for 5G, what an eSIM is, and generally tell you everything else you need to know about SIM cards.

1. SIM Card Sizes

1.1 Why are there different-sized SIM cards?

There are different-sized SIM cards because it has become increasingly desirable to have smaller SIM cards, since that frees up more space in a phone (or other device) for other tech, without making the phone larger.

However, while that means that the most common SIM cards are a lot smaller than a standard SIM card, the older, larger SIM card sizes are still in use too in some older devices, and in some devices that don’t need to make the most of their space.

1.2 What are the different SIM card types?

There are five common SIM card types, which are as follows:

Nano SIM

A nano SIM is the smallest removable SIM card size, and it’s also the most modern (other than eSIMs, which we’ll get to further down) having been introduced in 2012. This is basically just a small integrated circuit with almost nothing around it, and it’s the kind used by the vast majority of modern devices.

Micro SIM

A micro SIM card is the middle size. These have more plastic around them than a nano SIM, but less than a standard SIM. They also have a slightly larger chip. In terms of smartphones, you might need one of these if your phone is over six years old, but they’re rarely used in recent years. Indeed, they were introduced in 2003, so they’re getting on a bit now.

Standard SIM

A standard SIM is the biggest SIM card size currently in use, and despite being thought of as the ‘standard’ it’s the most rarely used. It has a large amount of plastic around the chip, and tends to only be found in the oldest of phones (and some other devices).

It was introduced back in 1996, and as the oldest of them it was the standard for a while – hence the name.

Note that standard SIM cards are also sometimes known as regular SIMs or mini SIMs – the latter because there was an even bigger credit card-sized SIM card available when these launched, but they’re no longer used.

Combi SIM

A combi SIM (sometimes called a multi SIM or trio SIM) combines all three sizes of SIM card into one, so you can easily just pop out the one you need.

This is the type you’ll typically be sent by a mobile network, so you don’t need to worry about requesting the right SIM card size. Note however that while you’ll be able to pop out whichever size you want, you won’t then be able to make the SIM card bigger again, so if you ever need to move up a size, you’ll either need an adapter (explained below) or to request a new SIM card.


An eSIM is an embedded SIM card (that’s what the ‘e’ is for) meaning that you can’t remove it from your phone or other device. This is the newest type of SIM and it’s found in quite a lot of modern handsets, such as the iPhone 14 range – along with many other iPhones – and the Samsung Galaxy S22 range.

These are actually even smaller than nano SIMs, therefore freeing up more space for other tech. That small size means eSIMs are also used in wearables such as Apple Watches and Samsung Galaxy Watches.

But the main advantages of eSIMs include making it theoretically much easier to change networks and plans – since you can’t change the eSIM in your device, it needs to be possible to change network while keeping the same card, so there’s no need to swap to a new one.

Plus, multiple networks and numbers can potentially be stored on an eSIM, so you can theoretically have multiple numbers on a single SIM. And you won’t need to worry about navigating all the different SIM card sizes detailed above.

While some phones use these, at the time of writing it’s always in addition to a removable SIM card slot (at least for phones sold in the UK), so you never have to use an eSIM on a smartphone. Few networks currently support them either, but it’s expected that these will become the standard SIM type eventually.

1.3 What are the physical dimensions for each SIM card size?

The chart below provides a clearer look at the exact size of each SIM card type. You’ll note that combi SIMs aren’t included and that’s because at their full size they’re the same size as a standard SIM, then if you pop out a smaller section it will match the relevant SIM card size below.

SIM Type Height (mm) Width (mm) Thickness (mm)
Standard SIM 25.00 15.00 0.76
Micro SIM 15.00 12.00 0.76
Nano SIM 12.30 8.80 0.67
eSIM 6.00 5.00 0.67

SIM Card Sizes Compared

Comparison of SIM card dimensions. Please note: nano SIMs and eSIMs are 0.09mm thinner than Standard SIMs and Micro SIMs.

1.4 What other differences exist between Standard SIM, Micro SIM, and Nano SIM?

No other differences exist between these SIM card types, it’s literally just the size. If there were other differences, then combi SIMs wouldn’t really be possible. An eSIM meanwhile is quite different, as detailed above.

2. Which SIM do I have, and which do I need?

Which SIM card you have will depend on a number of things. If you received one recently it’s likely a combi SIM, since that’s what networks tend to supply.

Failing that, unless it’s one that you’ve had for many years it’s probably a nano SIM, since they’ve been the most common for 6+ years.

However, to tell for sure just look at the picture near the top of this article and compare the SIM card types to yours – remembering that a mini SIM is another name for a standard SIM, and that an eSIM is embedded into the phone.

As for which you need, that will depend on your device, but the same general logic applies – for most modern smartphones, you’ll want a nano SIM. However, since networks supply combi SIMs you shouldn’t need to specify – just order one of those and then when it arrives you can pop out the right size for your phone.

The exception is if you want to use an eSIM, in which case you will usually need to request one – though many networks don’t support them.

3. SIM adapters and DIY downsizing

If you have the wrong SIM card size for your phone, then wherever possible the best thing to do is simply to request a new one from your network and get your number transferred to that.

However, there are alternative options. If your SIM card is too large for your phone, then you can buy a SIM card cutting tool. These tend to look a bit like a stapler, but they trim your card down to the correct size and shape.

If on the other hand your SIM card is too small for your phone, then you can get a SIM adapter. This is a plastic frame that you can put your SIM card in, to essentially upsize it to micro or standard size.

Both of these tools can be purchased, and some independent phone accessory stores and the like also offer SIM card cutting services. However, there’s always a risk of damaging the card when cutting it, so we don’t recommend it.

Of course, none of these solutions apply to eSIMs either – an eSIM only comes in one size, but if you want to switch to or from an eSIM then you’ll have to contact your network.

4. Do I need a new SIM card for 5G?

In most cases you won’t need a new SIM card to access 5G – if you have a 5G plan and a 5G phone, then your current SIM card should connect to 5G networks just fine. Your network may send a software update to your SIM card when it detects that you’re trying to connect to 5G, but that’s all.

Having said that, O2 claims at the time of writing that you will need a new 5G SIM card on its network. This won’t be true in all cases as it now often provides 5G SIM cards, but if for example you bought a 5G phone from the network before October 17th 2019, then you’ll need to switch to a new 5G card.

O2 seems to be an outlier though, as Three, EE and Vodafone all claim that your current SIM card will work for 5G. MVNOs such as Tesco Mobile and Virgin Mobile also claim that you won’t need to switch SIM card, though some others don’t specify one way or the other at the time of writing. So if in doubt, check with your network.

While we’re on the subject, it’s worth noting that you’ll still be able to connect to 4G and 3G networks with a 5G SIM card/plan, so you won’t lose access to the older technologies by upgrading to the newer ones.

5. FAQs

What are the different SIM card sizes?

The different removable SIM card sizes include nano SIM (which is the smallest), micro SIM (which is the middle size), and a standard SIM or regular SIM (sometimes called a mini SIM), which is the largest. There are also eSIMs, which are even smaller than nano SIMs, but they’re built into the phone, so you won’t see them.

Where can I buy a SIM that fits any phone or tablet?

Mobile networks supply something called a combi SIM, trio SIM or multi SIM, which includes all three possible removable SIM card sizes. This is usually offered as standard.

Can I put any SIM in my device?

No, you need the right size SIM card, which in most cases will be a nano SIM. If your device is locked to a specific network, then you also need the SIM card to be for that network – or to unlock your device.

Do SIM cards fit all phones?

All mobile phones use SIM cards but they don’t all use the same size ones, so you’ll need one that’s the right size for your phone. In most cases this will be a nano SIM.

Which phones use a nano SIM?

Most smartphones made from around 2015 onwards will use a nano SIM card. That includes big name handsets like the iPhone 14 range, iPhone 13 range, iPhone SE (2022), Samsung Galaxy S22 range, Samsung Galaxy S21 range, OnePlus 10 Pro, and many, many more.

What is the most common size SIM card?

Nano SIM cards are the most common size – most smartphones made from around 2015 onwards use a nano SIM card.

Can you convert a standard SIM to a nano SIM?

Yes, you can use a SIM card cutting tool to convert a standard SIM to a nano SIM. However, this isn’t recommended as it risks damaging the SIM card. In general you’re better off requesting a new SIM card from your network.

What size is a mini SIM card?

A mini SIM card is another name for a standard SIM. It was originally called a mini SIM because when it first launched there was a larger full-size SIM card in use too, but these larger ones are no longer used, so mini SIMs have become standard SIMs.

What is a SIM card adapter?

A SIM card adapter is a piece of plastic that you can place a micro or nano SIM card into to convert it into a larger size.

What happens if you take out your SIM card and put it in another phone?

If you put your SIM card in another phone then – as long as the card and phone support the same network – people will then be able to call and text you on that phone, and you’ll be able to make calls and send texts of your own from it, using the same network and allowances as you had on your old phone.

Phone numbers and other data may also be transferred along with the SIM card, if they were saved to the card.

What is a combi SIM?

A combi SIM is a SIM card that contains all three possible removable card sizes, with perforations allowing you to pop out the size you need. These are sometimes called trio SIMs or multi SIMs.

Are SIM cards universal?

SIM cards all contain the same tech; however they vary in size, and are typically locked to a specific network.

Do I need a new SIM card to connect to 5G?

In most cases you won’t need a new SIM card – your old one should work fine. However, on some networks (such as O2) a switch may be required. If in doubt, check with your network.

Can 5G SIM cards connect to 4G networks?

Yes. A 5G SIM card can still connect to 4G, 3G, and 2G networks. In fact, most 4G SIM cards already support 5G, so a ‘5G SIM card’ isn’t really a different thing.

What are nano-SIM, micro-SIM cards, their differences, how to make them from ordinary and one from another


  • 1 Introduction
  • 2 Varieties of SIM-cards
    • 2.1 Mini-SIM
    • 2. 2 micro- SIM
    • 2.3 Nano-SIM
  • 3 How to change the size of the SIM card
    • 3.1 We contact the telecom operator
    • 3.2 We go to the workshop
    • 3.3 We cut it manually according to the template
  • 4 Conclusion


No mobile device can operate on a carrier’s network without a small chip, commonly referred to as a SIM card. This is a small chip surrounded by plastic. It contains all the necessary data to identify a subscriber on the network, and also allows you to save some user information – for example, a list of phone numbers.

The SIM card is an intermediate link between the subscriber and the telecom operator

There are several types of SIM cards that differ in size. And the newer the standard, the smaller the card. The latest models are increasingly using smaller SIM cards, so when buying a new phone, the issue of adapting a SIM card becomes relevant. In this article, we suggest that you familiarize yourself with the standards of SIM cards, understand what is the difference between them and how to reduce them for use in a new device.

Types of SIM cards

There are three main formats: mini, micro and nano. What are they?


Standard card format. Used in most modern phones. In everyday life, the name without the prefix “mini” is popular. The dimensions of such a card are 25 × 15 mm. She does not need to be adapted, even if she is more than one year old. Just plug in and use.


Compared to the previous type, micro-SIM has smaller dimensions – 15 × 12 millimeters. It was first used in the iPhone 4. Recently, new devices are increasingly supporting this particular format. When buying a new phone, it is easy to cut off from a regular SIM card.


The latest, smallest SIM card used in the latest iPhones and iPads, as well as flagship Android models. Nano-SIM looks like a chip without plastic around. The dimensions of the card are small – 12×5 mm, so it is more difficult to adapt from larger formats.

Currently, most operators provide just such SIM cards, but if you have an old-style SIM card, we’ll tell you how to make a nano-SIM out of it a little below.

How to change the size of the SIM card

There are several options for changing the size of the SIM card: order a new one from your operator, contact a telephone workshop, or cut a regular card yourself. In the latter case, there is a risk of damage to the card due to inexperience, and then the responsibility for its damage will fall on you.

We turn to the telecom operator

The easiest and surest way. All you need to do is come to the communication salon with your phone and passport and order the SIM card replacement service. You will receive a new card in a suitable format, while your phone number, balance and connected services will be saved.

Recently, operators offer subscribers multi-format SIM-cards that are suitable for all types of phones. The outer shell is a mini-SIM, you can squeeze out a micro-SIM or nano-SIM from it along the indicated dotted line. You do not risk anything and use communication services without any problems.

This service is absolutely free. In some cases, you need to pay a small amount, which will remain in your account. This option is offered by the Tele2 operator.

Let’s go to the workshop

If for some reason you can’t contact a communication salon or don’t want to wait for a new card to be sent, you can cut it at any workshop. This will be done using a device similar to a stationery stapler, inside which a SIM card is inserted, and with one click the excess ends are cut off. Such a service is inexpensive, and in some workshops it is completely free.

Cut by hand according to the template

If the previous two methods are not available to you, try to do it yourself. To do this, you will need scissors, double-sided tape, a ruler, a pencil or a felt-tip pen, and the SIM card itself. You do not have to measure millimeters and calculate something, just use the template popular on the World Wide Web. Download it from the link and print at 100% scale on A4 paper. It can be used to make micro and nano-SIM.

  1. Using double-sided tape, carefully stick the SIM card on the marked place, making sure that it completely matches the picture. Do not press hard, otherwise you will not peel off later.
  2. Draw long horizontal, vertical and diagonal lines with a pencil or marker. The dimensions of the format you need will be marked on the SIM card.
  3. Trim excess plastic as carefully as possible along the lines you have drawn.
  4. With sandpaper or a file, carefully trim the cuts, round off the edge, as indicated in the diagram.
  5. Remove the tape and insert the SIM card into the phone.

The whole process will take a few minutes, so don’t rush to avoid cutting off too much. To facilitate your work on the same template there is a photo showing how to properly attach the SIM card. Don’t be afraid, you will succeed.


Now you know how SIM card formats differ and how they can be adapted. Of course, the most reliable option is to contact the communication salon. But if you don’t want to wait too long, try trimming by hand using a template.

Which SIM card format does your device support? How did you resize? Did you manage to do everything yourself? We are waiting for your answers in the comments.

How to make a micro SIM – the easiest and easiest way

Every year there are more and more owners of Apple products (especially iPhone and iPad), their requests are growing, technologies are improving, but the same question remains “ how to make micro sim “? A microSim card differs from a standard one in smaller sizes, which makes you think about changing or adapting the card after buying an iPhone or iPad. The easiest option is to go to the office of one of the mobile operators and ]]>choose a tariff]]>, which comes with a card of the required format. Now, many operators also offer their subscribers to replace a standard SIM card with a micro one, but the procedure is usually not free (though not expensive), so it makes sense to think about an alternative option and try to make such a replacement yourself, with your own hands.

For making a micro SIM card with your own hands we need:

  • scissors;
  • sharp knife;
  • ruler;
  • blank sheet of paper;
  • scotch;
  • pen or pencil;
  • standard sim card.

In order to cut the micro SIM, we will use the following pattern:

The fact is that the contact area on the micro SIM card is almost the same as a regular card. The main difference is the size of the plastic part in which the chip is placed. It is precisely by reducing the plastic part that we will adapt our SIM to work in the iPhone and iPad. Before you start creating our work of art, do not forget to activate it if the SIM card is new and has not yet been used (by the way, if you plan to use 3G Internet in your device, then I advise you to read the following materials:

  1. ]]>3G Internet from PeopleNet]]>.
  2. ]]>Intertelecom – 3G Internet]]>.
  3. ]]>3G tariffs from CDMA ua]]>.
  4. ]]>3G Internet TriMob from Ukrtelecom]]>.

Making a micro SIM with your own hands

1. To begin with, we take a pre-prepared sheet of paper, print out the template that was shown in the figure above. Next, we take a standard SIM card, put it on a sheet with a template so that the line on the template coincides with the edges of the future microsim. After that, we take a pencil or a pen (if a pencil, then a well-sharpened one), we circle the standard card well so that traces of the contour can be seen on the back of the sheet. As a result, you should get something like the figure below:

2. Turn over a sheet of paper and the edges (outline) of the SIM card will be visible on the reverse side. We will need them in order to more accurately position our SIM card on the sheet. We take adhesive tape and fix the card on paper exactly as in the figure below:

template. The best option is to do this procedure only once. Take your time, draw lines with a knife neatly, evenly. The result is below:

4. Our next step is to remove the prepared map from the sheet. Then we take scissors and carefully cut off the excess plastic along the contour, thus obtaining an almost finished micro SIM . I do not advise you to be very zealous when cutting. It’s better to cut a little less, and then, if necessary, fit it to the size of the slot in the iPhone or iPad. Otherwise, you can overdo it and have to order a new chip.

Our last action is removing bumps and polishing the edges. Do it in any way convenient for you. That’s all! The map is ready to be used in your device! Agree that making micro SIM with your own hands is as easy as shelling pears!

We make a card of the required format ourselves – video instructions

If you find it difficult to understand the instructions for creating a micro sim for your phone on your own, then I suggest you watch a video on which everything is described in detail. In order to cut a micro-sim, you will need 10 minutes of free time, sharp scissors, the card of your Ukrainian telecom operator itself, a ruler and a little careful work. Everything is quite simple, if you do not rush and follow the video instructions.