Your Mac's serial number is a unique identifier that distinguishes your Mac from all others. You have to provide your Mac's serial number when requesting warranty service. You may also want to look up your Mac's serial number if you're reporting it stolen.

The easiest way to find your serial number depends on your situation. If your Mac turns on, you can find the serial number right in the interface. If it doesn't turn on, you'll need to locate it on the case or original packaging. And if you don't have access to your Mac at all—say, it's been stolen—you can probably still find the serial number through Apple's website.

If Your Mac Turns On

If your Mac is working properly, finding the serial number is easy. Just click the Apple menu icon at the top of the screen and select "About This Mac".

You'll see the serial number displayed along with your Mac's model number, hardware specifications, and the version of macOS you have installed.

If Your Mac Won't Turn On

Your Mac's serial number is printed somewhere on the Mac itself, so you'll be able to find it if you can't turn your Mac on.

Flip over a MacBook and you'll see the serial number printed on the Mac itself, near the "Designed by Apple in California" text. On a Mac Mini, you'll find the serial number on the bottom. On the Mac Pro, you'll find it on the back panel.

If You Don't Have Your Mac

If you don't have access to your Mac, you can still find the serial number in a variety of locations.

If you signed into your Mac with an Apple ID account, the serial number is tied to your Apple ID account online. Head to the Apple ID account website and sign in with the Apple ID account you used on the Mac. Click the name of the Mac under "Devices" on the page that appears and you'll see the Mac's serial number.

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If you enabled Find My Mac on the Mac and it's been stolen or misplaced, you can track or lock it using the Find My Mac feature in iCloud.

If you still have the box your Mac originally came in, look on the box. The serial number is printed on the barcode label on your Mac's original packaging.

The serial number is also printed on the purchase receipt if you purchased your Mac from an Apple Store in person or in the email receipt if you purchased it from Apple's online store. Some other stores may also print the serial number of your Mac on the receipt, so check the receipt no matter where you bought your Mac from.

Also, if you've ever submitted a warranty or service request for the Mac, you'll see the Mac's serial number displayed in the Apple Store service confirmation email.

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