Refer to Find the serial number of your Apple product - Apple Support
Learn how to find the serial number of an iPhone, iPad, iPod, HomePod, Mac, or other Apple product.
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Depending on the product, you can find your serial number:
On the surface of your product.
In iTunes, if your product syncs with iTunes.
On a Mac, by choosing About This Mac from the Apple menu.
On an iPhone, iPad, iPod touch, iPod, or Apple Watch, in Settings > General > About.
If you don't have your product or it won't turn on
If you have your product's original packaging, you can check the barcode to find the serial number.
If you have an iPhone, iPad, iPod touch, or iPod, you can get the serial number from the Devices tab in iTunes preferences.
You can also find your product's serial number on the original product receipt or invoice.