iOS simulator screen size not equal to window size
Now It's more flexible with Xcode 9- Simulator. You can pick &amp; drag any corner of simulator to resize it and set it according to your requirement.

Look at this snapshot:



Note: With Xcode 9.1, Simulator scale options are changed.

There are several other ways also, to scale your simulator.

Keyboard short-keys:
 According to Xcode 9.1

Physical Size       ⌘ 1      command + 1
Pixel Accurate      ⌘ 2      command + 2


 According to Xcode 9

50% Scale           ⌘ 1      command + 1
100% Scale          ⌘ 2      command + 2
200% Scale          ⌘ 3      command + 3



Simulator scale options Menu:
Xcode 9.1


  Menubar  >>  Window  >>  "Here available options for simulator scaling" (Physical Size &amp; Pixel Accurate)




Xcode 9.0


  Menubar  >>  Window  >>  Scale  >>  "Here available options for simulator scaling"





Using Terminal Command
Follow these steps to scale simulator using terminal commands


Close/Quit simulator. (if open)
Open Terminal app (using Spotlight search, Press ⌘ + SPACE to open spotlight search)
Copy following text and paste it next to terminal cursor.


defaults write ~/Library/Preferences/com.apple.iphonesimulator SimulatorWindowLastScale "0.3"


Open 'Simulator' (Run your iOS project using Xcode).


You will find simulator scale update.