Various online services offer ways to shrink PDFs. You don’t have to download any programs or install any software. You simply upload the relevant PDF to the provider’s website or server. A few seconds later you can download the file again, ideally with a small file size and good quality.

Advantages of the online services: They offer quick access and dispense with the hassle of installing small additional programs that clutter up the computer. But you should also be aware of the disadvantages: Since you are uploading your file to a foreign server on the Internet, there is an increased risk to data security. In addition, you cannot always make settings for the type and strength of compression and thus not influence the image quality, for example. We took a closer look at the most common providers and their online tools:

  • AnyPDF
  • PDF Compressor
  • Small PDF
  • Online2PDF
  • PDF2Go
  • PDF24

Shrink PDF with one click

The AnyPDF compression tool reduce PDF file size without losing quality by an average of 30 percent and informs us of this immediately at the end. However, this is primarily at the expense of image quality. The user cannot make manual settings.

The PDFCompressor compresses immediately after the upload without further request and proudly displays the results in percent. Although the provider promises on its website that, unlike other providers, it will not reduce the resolution of the images, but the quality of the images suffers greatly here too. The file sizes are pleasantly small.

The provider SmallPDF only compresses one PDF after the other, the inclusion of several pages and files in one step is only possible with the Pro version. In our test, the processing is surprisingly fast and the compression strength is lower than with the other two providers.

Tools that allow manual intervention

Other compression tools such as online2pdf.com let the user intervene in the compression. Settings for quality, resolution and color mode of the images are possible here. It looks similar with PDF2Go. The user can also influence the compression with this tool – via predefined setting sets. With pdf24 Tools there are also a few buttons that the user can use to influence the type of compression.

Basically, there is no winner with the tools. Because the result always depends on the content and format of the PDF to be reduced.