Please follow the steps below to find out the capacity in gigabytes (GB) of an iPhone:
1) Tap the Settings icon on the iPhone's home screen.
2) Select the General option.
3) Then press About for information on your iPhone.
4) The total storage size of your iPhone in gigabytes (GB) is shown under Capacity.
It's important to remember that the indicated storage capacity will always be slightly less than the actual capacity due to system usage.
Additionally, if you scroll to the bottom, you can see how much storage you have available on your iPhone.
And remember, you can unlock your iPhone to use it with any carrier without losing the warranty at doctorSIM.