Size. As we said above, the iPhone 8 and the iPhone X are both smaller than the iPhone 8 Plus (and other Plus models). The iPhone X measures 143.6mm by 70.9mm, and is 7.7m thick. The iPhone 8 is 138.4mm by 67.3mm and is 7.3mm thick.
Then, what cases fit the iPhone X?
3 Answers from the Community The XS case will fit on an iPhone X but with a tiny gap around the bottom and right-hand-side of the camera bump on the back (about half a millimetre, not really noticeable unless you look for it). However the X case will not fit on an iPhone XS, as the XS camera bump is slightly bigger.
Subsequently, question is, what iPhone is the same size as the X?
The iPhone XS has the same dimensions and same size display as the iPhone X. This means most iPhone X cases should fit the iPhone XS, but you should double check with your case's manufacturer before ordering any new device.
Are iPhone 7 and 8 the same size case?
Your iPhone 7 / 7 Plus case will likely fit your new iPhone 8 / 8 Plus. The dimensions of the new i8 phones are very close to the dimensions of the i7. The differences are so small that if you're rocking a 7 case, you should be good to use the same case for your iPhone 8.
Is it worth upgrading from iPhone 8 to XS?
The iPhone XS is a lot more expensive than the 8 so you need a lot of reasons to upgrade or choose it out of the two. So it's understandable if you want the smaller screen and home button on the iPhone 8. It's a much better value option, that's for sure.