When Digital Trends got the refurbished Apple Watch 4, it was perfect-40mm case size and light blue sports strap. The only problem is that even in the most compact environment, the band is too big. It must either slide it onto the arm to keep it still, or let it fall onto the wrist bone like a bracelet. In the end, this loose strap was replaced by a Sport Loop that could be tightened to a perfect fit.

Apple has realized that a one-size-fits-all style is not for everyone. Last year, the company launched the Solo Loop and Braided Solo Loop in its huge series. Unlike the infinitely adjustable Sport Loop, solo or braided straps — not to mention the buckle or even various sports straps — should be more accurately calibrated. If your watch has a Solo strap, our recent article explains how to measure the wrist specifically for it.

Now, for all other strap types, we provide some important background information and then show you how to measure your wrist and the options for choosing the right strap for you.

Apple conveniently aligns the strap and face size, making the task of choosing a strap easier. The smaller Apple Watch is 38 mm or 40 mm, and the larger Apple Watch is 42 mm or 44 mm, measured from top to bottom, depending on the series. The Apple Watch strap that fits the 38mm Series 3 Apple Watch also fits the 40mm Series 6 model. Similarly, a strap that fits the 44mm series 5 is also suitable for the 42mm series 2. In other words, all straps for 38mm and 40mm cases are compatible with each other, as are all straps for 42mm and 44mm cases. Female wrists average between 140 mm (5.5 inches) and 170 mm (6.7 inches), while male wrists average between 165 mm (6.5 inches) and 195 mm (7.8 inches).

The best way to calculate your wrist size is to use the Apple Watch strap sizing chart—this watch will help you whether you plan to buy an Apple branded watch strap or not. Apple has its own instruction sheet that can provide you with step-by-step instructions on how to measure the strap size. It includes printing a model of the strap, cutting it out, wrapping it around your wrist, and writing down its numbers.

Some bands are easier to measure than others. For the adjustable Sport Band and Sport Loop, the options are S/M (short band) or M/L (long band). However, not all bands fall into this category. For example, you cannot adjust the Solo Loop, so you need to buy the correct size. Even without a printer, you can cut out a piece of paper or a piece of rope, mark the size of your wrist, and then use a ruler to measure it. Then, enter the measurement value on the Apple website to get the correct size by clicking the "Start Measurement" button.

Apple and many third parties have built a variety of strap types for each size of watch, which can easily be divided into two size categories. Certain frequency bands are only available for limited models. For example, Solo Loop and Braided Solo Loop straps are only compatible with Apple Watch SE and Apple Watch Series 4 or later. The strap fits only the selected case size and is not compatible with other case sizes, so the size 5 of the 40mm case is not suitable for the 44mm case, and vice versa.

The Apple Watch adapter market is booming, and these devices allow you to connect your old strap to your new Apple Watch. There are two main types of adapters: tubular designs with screws, and interchangeable adapters with traditional spring bars in the middle. You may need a simple tool-unless you have a quick release strap that already contains spring bars. These adapters are available in a variety of sizes and finishes to match your watch. They are as easy to use as replacing the original Apple watch strap. You can find them on Amazon or Etsy and many other vendors.

Although in theory you can use an adapter to connect a larger strap to a smaller Apple Watch—for example, connect a 42mm strap to a 38mm watch and vice versa—but force the strap to the wrong size watch On the shell is not a good idea. It looks awkward, an oversized adapter may interfere with your sleeves or other clothes, and an undersized strap may cause gaps. It's easy to pair an Apple Watch strap of the right size with the watch of your choice or use an adapter to continue wearing some of your favorite old straps (if they fit).

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