Apple Watch 7 sizes — what you need to know

Apple Watch 7
(Image credit: Future)

The Apple Watch 7 sizes are a little confusing. For the first time, shoppers will have 41mm and 45mm models to choose from.

This is the second time Apple has pulled a smartwatch size change. The Apple Watch 4 increased to 40mm and 44mm versions from the Apple Watch 3's 38mm and 42mm options. Now, the Apple Watch 7 is positioned to become the best Apple Watch yet for users craving larger wrist candy. 

The only nod Apple made to the Apple Watch's size alterations was mention of watch band compatibility. The company has promised all existing Apple Watch bands will work with the Series 7 and its expanded displays, so if you've amassed a collection of cool straps, it won't be worthless should you decide to upgrade.

Now that the Apple Watch 7 is here, heres what you need to know about the new Apple Watch 7 sizes. 

Apple Watch 7 sizes explained

The Apple Watch 7 comes in 45mm and 41mm sizes. The case growth is hardly noticeable, though enough to justify changing the 44mm and 40mm sizes from previous models.

Apple Watch 7 new sizes — what it means for Apple Watch bands

When you shop for Apple Watch bands now, you can choose between the 41mm and 45mm case sizes for compatibility. According to the company's advice, the 41mm straps should work for 38mm and 40mm cases, while the 45mm straps should work for 42m and 44mm cases. In other words, the new bands work with Apple Watch Series 3 and newer, including the midrange Apple Watch SE. Looks like there's some similarity between strap and watchOS 8 compatibility, huh?

Whether you're buying new bands for your current Apple Watch or want to know what will happen to you current bands when you buy a new Apple Watch, you'll need to do some research.

Before you buy a new band for your Apple Watch 6, Apple Watch 5 or any other Apple Watch model, take note of your smartwatch's size. If you don't know it off the top of your head, check your wrist — the size is listed on the smartwatch's underside. 

If your Apple Watch is 38mm or 40mm, buy a 41mm band. If your Apple Watch is 42mm or 44mm, buy a 45mm band. The smaller sizes and larger sizes are grouped together in terms of compatibility, though this tip doesn't apply to Apple Watch Series 2 or earlier.

For those planning to buy the Apple Watch 7, or who want to buy a pair of straps for someone else planning to buy the Apple Watch 7, the strap size options will match the Apple Watch 7 case size options. You might want to choose your new Apple Watch size in respect to the bands you already own, too.

Kate Kozuch

Kate Kozuch is the managing editor of social and video at Tom’s Guide. She writes about smartwatches, TVs, audio devices, and some cooking appliances, too. Kate appears on Fox News to talk tech trends and runs the Tom's Guide TikTok account, which you should be following if you don't already. When she’s not filming tech videos, you can find her taking up a new sport, mastering the NYT Crossword or channeling her inner celebrity chef.

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