The term eSIM is ambiguous - it can refer to a special SIM form factor (MFF2) that is smaller than a nano SIM card or eSIM can refer to the capability to update a SIM card in the field. While this article talks mainly about the difference in the form factors, please feel free to check for what is an eSIM article that is focused on the technology that allows to update SIMs in any form factor over-the-air.
Get in touch with our IoT experts
Discover how emnify can help you grow your business and talk to one of our IoT consultants today!
What Types of SIMs are There? Different SIMs and Form Factors Explained
The humble SIM card has evolved far beyond its original design, becoming a critical component in ensuring seamless connectivity across devices and networks globally. From the traditional, physical SIMs to the innovative, embedded eSIMs, the technology has adapted to meet the diverse and expanding needs of IoT applications.
What is an eSIM?
Traditionally, if you wanted to switch your cellular device's carrier you had to replace the SIM with one from the new carrier. With phones and tablets, this is a simple task. However, for thousands of remotely deployed IoT devices, swapping out SIMs is problematic, especially for devices with embedded SIM form factors that are soldered. In such cases, the SIM is stuck in the device.