A subscriber identity module, also called a SIM card, is a miniature circuit board that stores information about your mobile phone number and service provider. It is not to be confused with a microSD card, which is used to increase the storage capacity of a mobile device. While most mobile devices already come with a SIM card, there are instances in which you’ll want to know what size your SIM your device uses – such as changing service providers or purchasing a SIM for international travel. This article will explain the different sizes of SIM cards that are currently available in the UK.
Standard SIM Card
The original, or “standard” SIM card is the largest SIM card available. It measures 15 x 25mm and is commonly used in older phones like the Samsung Galaxy S II. Being the “first form factor” of the SIM protocol, the standard SIM card is less secure than newer SIM cards.
Micro SIM Card
As its name suggests, a Micro SIM card is smaller than a standard SIM card, measuring 12 x 15mm. It is usually available in “dual cut” format, where the smaller card pops out from the centre of a standard-sized SIM card. The micro SIM card was developed by the European Telecommunications Standards Institute for use in devices that are too small for regular (standard) SIM cards. Many high-end smartphones, including the iPhone 4, use the micro SIM. The micro SIM card is more secure and supports a more comprehensive address book than the standard SIM.
Nano SIM Card
The nano SIM card is the smallest type of SIM card available, measuring a minuscule 8.8 x 12.3mm. It is used in the latest mobile devices. As with micro SIMs, nano SIMs are usually provided in the form of a dual cut card. The iPhone 6S and Samsung Galaxy 9 are among the smartphone models that require the use of a nano SIM. The nano SIM first appeared with the release of the iPhone 5.
How Do I Know Which Type of SIM I Need?
All three of the SIM card types explained above function in the same way from a technical standpoint. The only difference between them is the amount of plastic housing surrounding the circuit board. That said, it’s important to select the right type of SIM card for your phone in order for the device to work properly. Choosing the right type of SIM card will depend on the type of device you have. As a general rule of thumb, basic and mind-level smartphones use micro SIM cards, while newer, high-end smartphones use a nano-sized SIM.
The easiest way to check what type of SIM your device uses is to refer to your phone’s user manual or check the manufacturer’s website. Another way to check what type of SIM a phone uses is to check the SIM card slot, which is usually located behind the phone’s battery. If you’re still unable to determine the proper type of SIM for your phone using these methods, contact your service provider.