Try this

Display display = getWindowManager().getDefaultDisplay();DisplayMetrics outMetrics = new DisplayMetrics ();display.getMetrics(outMetrics);float density  = getResources().getDisplayMetrics().density;float dpHeight = outMetrics.heightPixels / density;float dpWidth  = outMetrics.widthPixels / density;

OR

Thanks @Tomáš Hubálek

DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();    float dpHeight = displayMetrics.heightPixels / displayMetrics.density;float dpWidth = displayMetrics.widthPixels / displayMetrics.density;

I stumbled upon this question from Google, and later on I found an easy solution valid for API >= 13.

For future references:

Configuration configuration = yourActivity.getResources().getConfiguration();int screenWidthDp = configuration.screenWidthDp; //The current width of the available screen space, in dp units, corresponding to screen width resource qualifier.int smallestScreenWidthDp = configuration.smallestScreenWidthDp; //The smallest screen size an application will see in normal operation, corresponding to smallest screen width resource qualifier.

See Configuration class reference

Edit: As noted by Nick Baicoianu, this returns the usable width/height of the screen (which should be the interesting ones in most uses). If you need the actual display dimensions stick to the top answer.

2021 Answer simplified for Kotlin:

val widthDp = resources.displayMetrics.run { widthPixels / density }val heightDp = resources.displayMetrics.run { heightPixels / density }

Or as one-liner:

val (height, width) = resources.displayMetrics.run { heightPixels/density to widthPixels/density }