Montreal, Сanada - May 28, 2015: 42mm 316L Stainless Steel Apple Watch with black Sport Band isolated on white background. The Apple Watch became available April 24, 2015 and is the latest device produced by Apple.
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How to Check Your Apple Watch's Battery Health
Although you don't need to check your Apple Watch's battery health regularly, keeping track of it is a good idea, especially if you're facing issues like random shutdowns or your watch’s charge doesn’t last as long as it used to. To check the battery health of your Apple Watch, you will need to check the maximum battery life that your device can offer.
1. Press the crown button to open the app drawer and head to the Settings menu.

2. Tap on Battery and select Battery Health.

3. You will find the maximum battery capacity as a percentage.
If the maximum battery capacity is above 80%, you need not worry, but if the battery health is less than 80%, regardless of how long you've owned the watch, you should consider visiting an Apple Store to get it replaced. One can expect a 1 to 3% drop in the battery capacity every month from the date of purchase.