This was the most useful part of the old system. The 4th and 5th characters typically represented the year and week of production.
Sign in to account.apple.com and select the Devices tab to see serial numbers for all linked hardware. apple by serial number
Older Apple serial numbers used a format that identified the year and week of manufacture. This was the most useful part of the old system
In the old system, if you posted a photo of your device’s "About This Mac" screen, a savvy observer could tell exactly how old your machine was based on the manufacturing code. By randomizing the string, Apple made the serial number a pure identifier, stripping away the public metadata of age and location. Older Apple serial numbers used a format that
Look at the back of the device, the underside of a Mac, or the SIM tray on certain iPhone models.
Apple typically etches the serial number directly onto the device. It is usually found on the back of iPhones and iPads, the underside of MacBooks, or inside the charging case lid for AirPods.