convert pixels to centimeters

Hi, I have a printed format and need to translate it to the screen (web page); so when the visitors print it from the web they get the same printed format I have.
Can you help me answering how many pixels are there in an A4 paper sheet?

thanks a lot!

How long is a piece of string?

All well put.

An A4 page (8.2 x 11.6 inches)
@ 300ppi = 2480x3508 pixels
@ 200ppi = 1653x2339 pixels
@ 100ppi = 827x1170
@ 72ppi = 595x842 pixels

Even the last one is too large to see at one time unless user is running 1152x864 screen rez (which proportionally few users do).

Mac