Every iPhone has a unique 15-digit number called an IMEI, or International Mobile Equipment Identity. You usually have no reason to know your phone’s IMEI number and can safely ignore its existence.

How to find the IMEI number on your iPhone using Settings

1. Start the Settings app.

2. Tap “General,” and then tap “About.”

3. Scroll to the bottom of the page, and you’ll see the IMEI number.

4. tap and hold the IMEI number for a second or two until you see the Copy bubble appear. Tap “Copy” and you can paste the number in a new Note

Gif Tutorial : 

How to find the IMEI number on your iPhone using the Phone app

1. Open the Phone app.

2. Dial *#06#.

3. The screen will immediately display your phone’s IMEI number. Tap “Dismiss” to close the page.