What Size Apple Watch Do I Have?

Trying to determine apple watch you have? Check out our quick and easy guide to help you figure out which model you have.

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There are two different size cases for apple watch 38mm and 42mm. But which one do you have? It’s easy to tell, and in this short article we’ll show you how.

Apple offers two different case sizes for the Watch, 38mm and 42mm, measured diagonally. But which one do you have?

It’s easy to tell. Just look at your Watch case. If it’s 38mm, it will say “38mm” on the back, near the bottom. If it’s 42mm, it will say “42mm” instead.

To be sure, you can also measure your Watch case yourself. Just use a ruler or a tape measure to measure the distance from one side of the case to the other. Again, if it’s 38mm it will measure about 3.8cm (1.5 inches), and if it’s 42mm it will measure about 4.2cm (1.65 inches).

If you’re still not sure which size you have, take a look at the bands that came with your Watch. The 38mm case takes 15cm (6-inch) bands, while the 42mm case takes 17cm (7-inch) bands.

The Different Sizes of apple watch

Apple watch comes in two different sizes, the 38mm and the 42mm. If you have a small wrist, the 38mm might be the better choice for you. If you have a medium to large wrist, the 42mm might be a better fit. There are also different band sizes that you can choose from.


The 38mm refers to the height of the watch face. For those with a smaller wrist, or who prefer a more delicate look, the 38mm is a good choice. It’s also 10.5mm thick, compared to 11.4mm for the 42mm model.


The 42mm case size is the only option for the Series 3 and apple watch models. It’s also an option for series 4 and Series 5, but you can also choose the smaller 40mm case size.

For context, the 40mm case is 11.4mm thick, 36.5mm tall, and 34.3mm wide. The 42mm case is 11.4mm thick, 39.3mm tall, and 36.4mm wide, which means it’s about 10 percent larger overall than the 40mm size. Both sizes have identical features otherwise.

The increase in size means you get a bit more screen real estate to work with on the watch face and in apps. It also gives room for a larger battery, which could improve battery life a bit compared to the smaller model — but in our testing, we didn’t find a noticeable difference between the two sizes in terms of everyday use.

How to Measure Your Wrist

To determine which case size is best for you, measure your wrist. Here’s how:
1. Wrap a measuring tape around your wrist.
2. Make a note of where the tape meets and measure that distance with a ruler.
3. Compare your wrist measurement with the case size descriptions below to find apple watch size.

Apple Watch comes in two different case sizes: 38mm and 42mm. You also have the choice of two different bands for each case size.
The 38mm case works well for people with smaller wrists or anyone who prefers a more delicate appearance to their watch. The 42mm case offers a more substantial feel and look, and provides more screen real estate for apps and complications

How to Determine Which Size is Right for You

In order to find the right apple watch for you, it’s important to first measure your wrist. To do this, wrap a measuring tape around your wrist at the point where you would normally wear your watch. Once you have your measurement, consult the sizing chart below to determine which Apple Watch size is best for you.

If you are between two sizes, it is generally best to choose the larger size. Keep in mind that Apple Watches have adjustable straps, so you can always adjust the fit if necessary.

Size Chart:
-38mm Case: Fits wrists up to 140mm
-42mm Case: Fits wrists up to 160mm


In conclusion, the size of your Apple Watch will depend on the model that you have. The Watch Series 1 and 2 come in 38mm and 42mm sizes, while the Watch Series 3 comes in 40mm and 44mm sizes. If you’re not sure which model you have, you can check by looking at the different photos on Apple’s website or checking the model number on the back of your watch.

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