You need a third-party (often called an IMEI checker). Services like * sickw .com * or * IMEI24 .com * offer deeper data for a small fee (usually $1–$5).
Look at the barcode sticker. You will see "Serial No." printed right next to the barcode. apple serial number finder
Remove your SIM card tray. On models from the iPhone 5c to the iPhone 13, the serial number is laser-etched on the inside of the tray. (Note: iPhone 14/15 removed this). You need a third-party (often called an IMEI checker)
But what if you can’t access the device? What if the sticker on the back has worn off? This is where an becomes your best friend. apple serial number finder