There is really a misconception of pixels and points. Pixels are relative to your own screen and are different form model to model.
You can have a monitor with a width of, lets say, 25" and you have on there 2000 px, but you can have another monitor of same size and this has only 1800 pixels. Or 2200 pixels.
Points are real lenghts, always the same. Unfortunately, the european and the us points are different, in Gutenbergs time or shortly afterwards each font foundry had their own size. So in the 18th century with the industrialisation, continental western Europe decided to use the Didot point of 1 Didot point = 0.37597151 mm. However, don't be fooled, this was not a strictly adhered to width. Many foundaries had slight aberrations: 0.376065 mm (0.0249% larger than Didot's point)—the traditional value in European printers' offices, 0.376 mm (0.0076% larger)—used by Hermann Berthold (1831–1904) and many others 0.37594 mm (0.0084% smaller)—Jan Tschichold (1902–1974), who used 266 points in 100 mm 0.375 mm (0.2584% smaller)—proposed in 1975, but hardly adopted. The different US-points were roughly 0.02 Points smaller.
And then the DTP was introduced: The desktop publishing point (DTP point) is defined as 1⁄72 of the Anglo-Saxon compromise inch of 1959 (25.4 mm) which makes it 0.0138 inch or 0.3527 mm. Twelve points make up a pica, and six picas make an inch.
It is impossible to have the exact transfer without an exact knowledge of the pixel size on your monitor. Stupidly enough most sales brochures are not delivering this measurements, so you need to find this out yourself. I use ffor this my Gimp, where there is under Preferences, then go to Display and you find a button to make an exact manual calibration. My Pixel is 101.02 x 99.93 of whatever. Then I put these figures under Default Image. My wifes Laptop has a pixel size of 106.516 x 106.573 whatever.
Wikipedia has some very comptehenisive information about the typographical points and the DTPs.