How do pixels convert to dpi?

300 dpi in pixels per cm or pixels per inch?

• im confused, but i need to put the setting on photoshop as 300 dpi or 12 pixels per mm. The only options are in pixels per cm and pixels per inch, so im not sure...

• Answer:

  D.P.I = dots per inch P.P.I = pixels per inch DPI is not the same thing as PPI - although Adobe Photoshop uses PPI to work out the print size of a document as though it was DPI. For all practical purposes the two are interchangeable. You can't adjust the DPI in Photoshop - because the DPI is decided by the printer. The DPI is the printer output resolution. PPI is the screen output resolution. Changing the PPI of an image alone won't change anything in an image - it will only affect the size the image displays at.