Android Convert Px to Dp (Video Aspect Ratio)

Instead of trying to infer the dp conversion factor from the screen's density classification, you can simply query it directly:

getWindowManager().getDefaultDisplay().getMetrics(metrics);
float logicalDensity = metrics.density;

logicalDensity will then contain the factor you need to multiply dp by to get physical pixel dimensions for the device screen.

int px = (int) Math.ceil(dp * logicalDensity);

How to convert pixels into dip(Density Independent Pixels) in Android

Hope this will be helpful

Resources r = getResources();
float dp = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PX, 69, r.getDisplayMetrics());

What is the difference between px, dip, dp, and sp?

From the Android Developer Documentation:

px

Pixels - corresponds to actual pixels on the screen.
in

Inches - based on the physical size of the screen.

1 Inch OR 2.54 centimeters
mm

> Millimeters - based on the physical size of the screen.
pt

> Points - 1/72 of an inch based on the physical size of the screen.
dp or dip

> Density-independent Pixels - an abstract unit that is based on the physical density of the screen. These units are relative to a 160
dpi screen, so one dp is one pixel on a 160 dpi screen. The ratio of dp-to-pixel will change with the screen density, but not necessarily in direct proportion. Note: The compiler accepts both "dip" and "dp", though "dp" is more consistent with "sp".
sp

> Scaleable Pixels OR scale-independent pixels - this is like the dp unit, but it is also scaled by the user's font size preference. It is recommended you
use this unit when specifying font sizes, so they will be adjusted
for both the screen density and the user's preference. Note, the Android documentation is inconsistent on what sp actually stands for, one doc says "scale-independent pixels", the other says "scaleable pixels".

From Understanding Density Independence In Android:

Density Bucket	Screen Density	Physical Size	Pixel Size
ldpi	120 dpi	0.5 x 0.5 in	0.5 in * 120 dpi = 60x60 px
mdpi	160 dpi	0.5 x 0.5 in	0.5 in * 160 dpi = 80x80 px
hdpi	240 dpi	0.5 x 0.5 in	0.5 in * 240 dpi = 120x120 px
xhdpi	320 dpi	0.5 x 0.5 in	0.5 in * 320 dpi = 160x160 px
xxhdpi	480 dpi	0.5 x 0.5 in	0.5 in * 480 dpi = 240x240 px
xxxhdpi	640 dpi	0.5 x 0.5 in	0.5 in * 640 dpi = 320x320 px

Convert px to dp and sp in /values/dimen.xml in Android

Check this -

1) What is the difference between "px", "dp", "dip" and "sp" on Android?

2) Android screen size HDPI, LDPI, MDPI

Hope it will help :)

How to get screen dimensions as pixels in Android

If you want the display dimensions in pixels you can use getSize:

Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int width = size.x;
int height = size.y;

If you're not in an Activity you can get the default Display via WINDOW_SERVICE:

WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();

If you are in a fragment and want to acomplish this just use Activity.WindowManager (in Xamarin.Android) or getActivity().getWindowManager() (in java).

Before getSize was introduced (in API level 13), you could use the getWidth and getHeight methods that are now deprecated:

Display display = getWindowManager().getDefaultDisplay(); 
int width = display.getWidth();  // deprecated
int height = display.getHeight();  // deprecated

For the use case, you're describing, however, a margin/padding in the layout seems more appropriate.

Another way is: DisplayMetrics

A structure describing general information about a display, such as its size, density, and font scaling. To access the DisplayMetrics members, initialize an object like this:

DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);

We can use widthPixels to get information for:

"The absolute width of the display in pixels."

Example:

Log.d("ApplicationTagName", "Display width in px is " + metrics.widthPixels);

API level 30 update

final WindowMetrics metrics = windowManager.getCurrentWindowMetrics();
 // Gets all excluding insets
 final WindowInsets windowInsets = metrics.getWindowInsets();
 Insets insets = windowInsets.getInsetsIgnoringVisibility(WindowInsets.Type.navigationBars()
         | WindowInsets.Type.displayCutout());

 int insetsWidth = insets.right + insets.left;
 int insetsHeight = insets.top + insets.bottom;

 // Legacy size that Display#getSize reports
 final Rect bounds = metrics.getBounds();
 final Size legacySize = new Size(bounds.width() - insetsWidth,
         bounds.height() - insetsHeight);

conversion from dp to pixel wrong

Use this

int pixels = getResources().getDimensionPixelSize(R.dimen.button_left_right_margin);

Android Convert Px to Dp (Video Aspect Ratio)