Standard SIM: Origin, usage & significance explained

Standard SIM: The foundation of mobile communication

The standard SIM or full size SIM was the first SIM card available on the market and is regarded as the foundation of mobile communication. It enabled access to mobile networks for the first time and made mobile phones suitable for everyday use. Although it is rarely used today, it remained indispensable for many years. In this article, we explain what a standard SIM card is, describe its characteristics and developments, and assess its current significance.

What is a standard SIM card?

The standard SIM is the first version of SIM cards and is also referred to as a full-size SIM card and known as form factor 1FF (“1st Form Factor”). With its dimensions of 85.6 × 53.98 millimeters, it is the size of a credit card. It was introduced in the early 1990s and was part of the first generation of mobile phones. 

The card offered basic functions, enabling registration on the mobile network and storing data such as contacts and network information. Although its size may seem impractical today, it was considered a technological advancement at the time. It marked the beginning of a development that led to increasingly smaller and more flexible SIM card formats.

The successors to the standard SIM card

Over time, mobile devices became smaller, and SIM cards had to adapt accordingly. This led to the development of a series of increasingly compact formats, following the standard SIM card. It is important to note that while the size changed, the chip and its function remained the same. The following overview shows a comparison of the formats:

The standard SIM was followed by the significantly smaller mini SIM (2FF), which was used in many cell phones in the 2000s. This was followed by the micro SIM (3FF) and the nano SIM (4FF), which consist almost entirely of the chip. The latest version is the eSIM. It is permanently installed in the device, no longer requiring a physical card.

Technical features of the SIM card as the standard form

Inside the credit card-sized plastic casing is a chip with a gold-colored contact surface. It performs the core functions of the SIM card and enables the device to register on the mobile network as it contains a unique identifier known as the IMSI number. Security features such as the PIN and PUK provide protection, whereby if the PIN is entered incorrectly multiple times, the card can only be unlocked using the PUK.

In addition, the full-size SIM card stores basic data such as phone numbers, SMS messages, and network operator settings. Communication with the mobile phone is handled through defined protocols, whilst basic encryption protects the data being transmitted. The standard SIM 1FF is compatible with the GSM network and meets all essential requirements for mobile telephony.

Practical use of the standard SIM card size today

In the 1990s, the full size SIM card became standard on the market and was used in the mobile phones that were common at the time. The card was inserted completely into the device, without a break edge or adapter.

Today, it is still used in isolated cases. Old GSM terminals, industrial systems, and machine controls often have a slot for the standard SIM 1FF format where it ensures reliable data transmission or remote control. In many of these systems, converting to smaller formats would be technically complex or economically unfeasible. A typical example is older alarm systems with GSM modules.

In everyday use, the standard SIM still plays a role as a carrier element for modern triple SIM cards. The standard format encompasses the smaller variants and allows flexible use depending on the device. Otherwise, its use is limited to nostalgic purposes. As a collector's item, museum piece, or functional component in old devices, it retains its place in the history of mobile communication.

Strengths and weaknesses of the full-size SIM card

The standard SIM card was well-suited for mobile communication in the 1990s. Its large format offered many advantages at the time, but is considered impractical by today’s standards. Especially when compared to smaller SIM formats, it becomes clear that it is technically outdated. The following overview summarizes the most important advantages and disadvantages:

Full-size SIM card as the foundation of the mobile world

The standard SIM 1FF format marked the beginning of mobile communication and laid the foundation for all further developments. Although it is now technically obsolete, its core principle continues in modern formats from Mini, Micro, and Nano SIMs, and finally to the eSIM.

Frequently asked questions about standard SIM (1FF)

What is a standard SIM card and how large is it? 

The standard SIM card is the original SIM card format and measures 85.6 x 53.98 millimeters, as the size of a credit card. It is also known as a full-size SIM card or 1FF.

What was the standard SIM used for in the past?

In the 1990s, it was used in classic mobile phones. It enabled voice calls, text messaging (SMS), and the storage of contacts. At the time, it was the standard in many devices.

Is the SIM standard card standard still in use today?

Hardly in everyday use, it still appears in certain niche applications. Industrial systems, older GSM terminals, or machines still use it in some cases, whilst it also appears as a carrier frame for triple SIM cards.

How can I tell if I have a full-size SIM or another format?

A standard SIM card is significantly larger than all other formats, matching the size of a bank card. Smaller SIM cards are often part of a multi-size card and can be broken out individually for use.