What is the size of a pixel?

Question

I assumed that a pixel is 1/72 of an inch.

But how can a 1080p picture fit on a 40" , 24" and a 12" screen?

Do pixel sizes vary according to screens?

Aren't the sizes constant?

If not, How can I find the screen size of a phone with width 480p and height 560p?

Answer 1

Pixel is a point on a grid, so its size varies depending on the resolution

To find out how many pixels are in a given resolution you multiply width by height

edit: https://en.m.wikipedia.org/wiki/Pixel

Answer 2

Not without the Dpi. pix/dpi=inches

Answer 3

Agreed, DPI is the key value​ in this case.

Answer 4

You can query your monitor to see what it says a pixels size is:
GetDpiForMonitor function
https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510(v=vs.85).aspx

Answer 5

your program shouldnt every need to worry about dpi. only really your printer should care. try qt or sdl or something?

Answer 6

yeah 480x854 px
(widthXHeight)
so 409,920 pixels.

Answer 7

A pixel does not have a fixed size. You're confusing them with typography points:

https://en.wikipedia.org/wiki/Point_(typography)

A pixel (as jay said) is just a point on a grid. It can be small and practically invisible, or it can be very large, leading to a blocky appearance of objects:

http://pre05.deviantart.net/cae3/th/pre/i/2012/170/e/9/mario_large_pixel_painting_by_rubiksphoenix-d544g81.jpg

Answer 8

@jay, @Bogdan Sass, @Michael Simnitt
Thank You!

Answer 9

You need to know the DPI of a screen (dots per inch)

Answer 10

@jay
Its not for a program, its for ValentinHacker's answer...

https://www.sololearn.com/discuss/470116/?ref=app

Answer 11

@jay
But she forgot to give me the dpi...

Answer 12

Can you now tell me how to convert ValentinHacker's answer to inches?

https://www.sololearn.com/discuss/470116/?ref=app

She posted 480x854 px as the size...