SIM standards

Advancements in mobile industry constantly set new standards, and today we’ll tackle changes in SIM (Subscriber Identity Module) standards through the stages of mobile industry development.

These SIM cards date from 1991. They were used all the way to 1996, and today we are just a relic of times passed – we don’t see them anymore. The size of these SIM cards was massive, and the easiest way to present it is to compare it to the sizes of today’s SIM cards. Exact dimensions were: 85.60 mm x 53.98 mm x 0.76 mm.

The 1FF SIM card:

Probably the most widespread, and also the most recognizable SIM standard dates from the 1996, and it found its use throughout mobile industry. This standard is more often than not considered as the “SIM” standard, while this is in fact not true – MiniSIM has far smaller dimensions, but the same layout of pins, and it is often shipped out within the 1FF SIM card frame.

The size of a MiniSIM card is: 25 mm x 15 mm x 0.76 mm, which is a huge improvement compared to the 1FF standard.

MiniSIM rules the market for a very long time – it stood tall for over 15 years. As the SIM (1FF) standard has not been used for quite some time, the MiniSIM has often been presented as the regular SIM, but in fact, it is the 2nd SIM card standard in the hierarchy.

The MiniSIM (2FF) card:

Design progresses, and one of the key points in modern smartphones is the size of the chassis itself, which forces manufacturers to think of new ways to lay out the components inside devices themselves in order to secure enough space. This can also be done by completely removing some components altogether (remember the “lack” of the 3.5mm headphone port in the iPhone 7?) In 2010 for the first time we had a chance to see a completely new SIM card standard in a smartphone. It was the MicroSIM (3FF) standard which found its way through the iPhone 4.
 

Although it is available since 2003, the first implementation of the MicroSIM (3FF) standards was in the iPhone 4 in 2010, and it was done precisely in order to shrink the device and save the space inside the device itself. The layout of pins on the card, as well as the thickness of it, have remained the same. This SIM standard was imagined to be a standard which could, through compatible adapters (the plastic around the connectors), also work on devices which use the MiniSIM (2FF) standard. This resulted in a huge number of “How-To” tutorials and videos on YouTube, which showed how to convert a MiniSIM (2FF) card into a MicroSIM (3FF) card and vice versa. The sole emergence of this standard in the iPhone 4 foresaw a new era for SIM cards, and all other manufacturers also adopted this change by migrating towards the new standard.

The size of the MicroSIM (3FF) card: 15 mm x 12 mm x 0.76 mm

The MicroSIM (3FF) card:

The market demanded that the devices become more compact and slimmer, and the next step was the NanoSIM card, the 4FF. It is a card that, for the first time, changed its thickness alongside length and width.
This SIM standard was unveiled in October 2012, and again for the first time it was implemented in an Apple smartphone – the iPhone 5. The layout of pins has once again remained unchanged, but this time the plastic around the pins was shrunk down to the bare minimum, only enough to prevent short circuit. The main reason the thickness was reduced was to make NanoSIM cards capable of being places in MicroSIM or MiniSIM adapters to make the compatible with older devices.

The size of the NanoSIM (4FF) card: 12.30 mm x 8.80 mm x 0.67 mm

The NanoSIM (4FF) card:

The next step in SIM standards development is eSIM (Embedded SIM). These are chips which are preinstalled into a device and which are not removable, making them permanently installed into a device. The electronic system of the card is identical to the one in 2FF and 3FF cards, but this time these are chips which are during manufacturing soldered to the motherboard of the device. All this has been still in the R&D phase since 2010, the standard has still not been implemented, and the only device that uses the eSIM combined with the NanoSIM card is the new Google Pixel 2, but eSIM definitely represents the future of SIM card standards.

In order to convert a NanoSIM card into a MicroSIM or a MiniSIM card, corresponding adapters are used, and they look like this:

NanoSIM -> MicroSIM

NanoSIM -> MiniSIM

MicroSIM cards can also be converted to MiniSIM cards using the appropriate adapter, which looks like this: