Compress & Resize

The Difference Between Compress & Resize

There are two main ways on how to make a PDF “smaller”. At, we provide both of these ways, but sadly they often get confused or mixed up.

Thus, we will bring some life into the darkness now! Find out what’s the difference between resizing a PDF and compressing a PDF is. 

Make A PDF Smaller In 2 Ways

Before we start going into detail with the exact distinction, lets have a look at what we mean when we speak of the “size” of a PDF. There are two different sizes we will talk about:

  1. File Size: The exact size of the document and the amount of space it will need on a hard drive
  2. Page Size: The aspect ratio of the page inside a PDF which can be A4, A5 or another standard like “Letter”.


The page size does not influence the file size. Thus, when changing the aspect ratio of a PDF, the file size doesn’t change. Changing the file size, likewise, does not have any effect on the page size of the PDF either. These two notions of “size” are thus completely independent.


Compress A PDF

Compressing a PDF means changing the content of the PDF to an extend. Especially the DPI and quality of images contained in the document are targeted here. There are other values being changed to make the file size of a PDF smaller as well, but those are usually not noticeable when you view the PDF.

Thus, compression is necessary for:

  • saving space
  • sending large files
  • transferring files to an USB drive
  • uploading files to a website
  • using the files in certain programs


Resize A PDF

When resizing a PDF, we do not target the file size, but the page size of the document. This means that resizing can change the aspect ratio of a page from, e.g., A4 to A5.

This is important when it comes to printing your document.



Compression Resizing
Changes File Size Page Size
Is For Uploading
Saving SpaceSending