Cheapest prepaid SIM cards- starting at $10

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The SIM card, which comes in various sizes, is a tool that has grown to become a part of everyday life.

However, the SIM card comes in one of three sizes, which can be confusing. After all, what SIM card fits your phone? How large is your SIM card slot?

In this guide, you'll find not only a brief definition of the SIM card but also details on the available SIM card sizes, a chart on handset SIM card slot sizes, and more information on the growth of SIM cards.

What is a SIM card?

A SIM card (subscriber identification module) is embedded within the SIM card tray in most cell phones. The SIM card contains your unique profile and other additional information, such as your phone contacts. The SIM card tells the tower and your carrier network that you are authorized to use the cell phone tower.

What are the different SIM card sizes?

There are 3 SIM card sizes - nano SIM, micro SIM, and standard SIM. Some phones are compatible with one size, while others only take a different size. Fortunately for many, quite a few carriers will distribute universal SIM card kits, meaning that you can pop out a SIM card of any size from the kit that will fit your phone.

Some carriers may offer what is known as a dual-cut SIM or dual SIM. A dual SIM is when two SIM cards - like the Micro SIM card and the standard SIM - are sold together in one card. So, if your mobile device needs a Micro SIM card, then you'll be able to pop the smaller Micro SIM card out of the larger Standard SIM card and insert the card into the SIM card tray.

SIM card size chart

SIM Type Length Width Height
Standard SIM card 25mm 15mm 0.76mm
Micro SIM card 15mm 12mm 0.76mm
Nano SIM card 12.3mm 8.8mm 0.76mm

Nano SIM card

Finally, we have the most current and smallest SIM card type available on the market: the Nano SIM card. The Nano SIM card is today's standard, acting as the SIM card for many flagship models.

The Nano SIM acts as the "fourth generation" (4FF) of SIM cards, measuring 12.3mm x 8.8mm x 0.67mm. Furthermore, this smart card was released in early 2012.

Micro SIM card

The Micro SIM card is known as 3FF or third form factor. It is the "third generation" of SIM card types, measuring 15mm x 12mm x 0.76mm. Micro SIM cards were introduced with the following purpose: fitting into devices that were too small for the previous generation of SIM cards.

Better yet, the Micro SIM is backward-compatible, featuring the same assets and design as the Standard SIM. Again, the only difference is the amount of plastic surrounding the chip.

Standard SIM card

The Standard phone SIM card, otherwise known as the Mini SIM card, belongs to the "second generation" of SIM cards - this is why it is also referred to as 2FF, or second form factor. The reason why it is referred to as the standard size is due to the fact that the full-sized first-generation SIM card, which was introduced in 1996, has died out.

The measurements of the Standard phone SIM card are 25mm x 15mm x 0.76mm.

Most new smartphones today do not require the standard SIM card.

Apple iPhone SIM card sizes

iPhone SE Nano
iPhone 6 Nano
iPhone 7 Nano
iPhone 8 Nano
iPhone X Nano
iPhone XR Nano
iPhone XS Nano
iPhone 11 Nano
iPhone 12 Nano
iPhone 13 Nano
iPhone 14 eSIM
iPhone 15 eSIM

Samsung Galaxy SIM card sizes

Galaxy S7 Nano
Galaxy S8 Nano
Galaxy S9 Nano
Galaxy S10 Nano
Galaxy S20 Nano
Galaxy S21 Nano
Galaxy S22 Nano
Galaxy S23 Nano

SIM card size FAQs


Overall, prepaid SIM cards come in three different sizes, though they aren't all that different from each other. The only differences lie in the amount of plastic surrounding the chip.

However, be sure to refer to our table above to find what SIM card you'll need for your phone. Of course, if you desire to keep your SIM card for the long haul, you'll probably want to look into a SIM card adapter or a cutter.

You can use our comparison tool to find the best prepaid SIM card.

SIM card FAQs

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