I created this 200x200px box in AI file (72ppi):

a screenshot of the box as 200x200px in AI

After saving it as PDF, the PDF opens in different resolutions on different apps.

Here it opens as 305x305px in Adobe Reader:

enter image description here

Here it opens as 268x268px in Google Chrome:

enter image description here

What's happening here? I wanted to do a web presentation in the popular 1920x1080px, but I noticed, that the 100% didn't fit the 1920x1080px screen in any application.

EDIT: I used LightShot printscreening tool to estimate the dimensions of the box.

  • not entirely sure what is happening in Reader, but I note that 200/72 * 96 is very close to 268px. So google is using a monitor pitch calculation of 96ppi. 72 and 96 are "magic" ppi numbers based on historical choices for monitors many years ago.
    – Yorik
    Commented Apr 29, 2021 at 13:58

2 Answers 2


What you see are the effects of the default resolution of the various PDF viewers. It used to be an idea to have the "real" view on screen (in other words, something appearing as 1 inch on paper should also be 1 inch on screen).

In Acrobat, you can set that resolution in the preferences.


A PDF is not the format for a "web presentation"

If you truly need it for the web, use a slideshow script. Do a search like this: https://www.google.com/search?q=full+page+web+slider

If you intend to use it on a live presentation, for example on a videoconference, simply press Ctrl+L using Adobe reader and it will be Full page.

A PDF is not a file format intended to be viewed on a web browser. That is an extra feature of the web browser.

Even on Adobe reader itself, the unit Px is not intended to be used as absolute units. The units are physical units like Inches or Centimeters.

The software is only asumming a size to display this physical units.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.