To distribute or transfer documents most prefer PDF format. But email services doesn’t allow you to attach files beyond certain file size limit, then no option is left for you as you’ve to search for freeware programs that compresses PDF file, if quality of output file doesn’t matter for you but still should be readable on PDF readers, then you should consider using Free PDF Compressor, not a web service but a program does what its name says. 

Free PDF Compressor

Download and install the program on your computer and launch it. It offers five compression settings. Select a setting and browse PDF file you want to compress and click on "compress" button.

Free PDF Compressor

Compression Settings

  • Screen – low resolution, screen-view-only quality, 72 dpi images
  • eBook – medium resolution, low quality, 150 dpi images
  • Printer – high quality, 300 dpi images
  • Prepress – high quality, color preserving, 300 dpi images
  • Default – a wide variety of uses, possibly larger output file

Once the compression process is over, Output file will be saved to same directory where you’ve selected PDF file from.

You might’ve got it already, if you select the first setting – Screen – low resolution, screen-view-only quality, 72 dpi images-  output file will be produced with low resolution, still readable in PDF Reader but not that much clearly as we found.

In our testing, it has compressed 9.3 MB file size to 1.24 MB. Free PDF Compressor works on Windows XP/Vista/7/8.