Quote Originally Posted by Midgardsormr View Post
It's pretty easy if you remember what "dpi" actually means: "Dots per inch." Dots = pixels (sorta, but for these purposes it's close enough). So if you have A4, which is 8.3" x 11.7", you need to know how many "dots" (pixels) fit into that area. 300 dots per 8.3" is 300 x 8.3 = 2490. That's only if you can print all the way to the edge, though, so probably plan on losing at least half an inch in each direction, making it more like 7.8 x 11.2.

7.8 x 300 = 2340
11.2 x 300 = 3360
But how does it translate into real size? what is 2340 pixels in cm? If dpi scales the actual width and height size, what is the reason for choosing it anyway, if i can just make default 72 dpi and make dimensions larger putting what i want in pixels.