SIM cards were once the size of a credit card; learning these facts will make your head spin.

Many smartphones today no longer require a physical SIM card, but once upon a time, SIM cards were the size of credit cards. This began in 1991.

If you've used a mobile phone, you're likely familiar with SIM cards. SIM cards used to be larger in feature phones, but with the advent of smartphones, their size decreased. Now, phones are available that support e-SIMs, eliminating the need for a physical SIM card. There was a time when SIM cards were the size of credit cards. Let's learn a little history about SIM cards today.

When did SIM cards originate?

The SIM card stands for Subscriber Identity Module (SIM). It connects the phone to the mobile network. The SIM card was first invented in Munich. In 1991, the smart card manufacturing company Giesecke & Devrient created the first SIM card. At launch, two variants of SIM cards were introduced. One was the size of a credit card, while the other was smaller. The larger SIM card was used in fixed car phones and early portable phones, while smaller portable phones accommodated the mini SIM card. The introduction of SIM cards offered users the option to switch their subscriptions between devices, a feature previously unavailable.

When did SIM cards become smaller?

SIM card sizes began to shrink in 2010, and even smaller SIM cards began to be introduced in 2012. Most smartphone companies designed their smartphone SIM card slots to accommodate these two sizes. Over the past few years, smartphone companies have begun shrinking the SIM card slot to accommodate more features in their phones. Subsequently, SIM card sizes continued to shrink. In 2017, e-SIM, a software version of the SIM card, was first introduced. Initially it was limited to wearable devices only, but now it has started being used in smartphones also.