Compressing PDF Files without Degrading Document Quality

Reduce the file size without compromising file quality and make archival and file transfer much more easier. SwifDoo PDF frees you from worries about file size limit.

Benefits of PDF compression

You can compress PDFs to make them smaller. PDF compression has two benefits: (1) faster transfer speed: compressing PDFs into smaller files prevents servers from slowing down; (2) storage efficiency: a smaller file takes up less space in the storage system.


No Data Loss and Reduced File Quality

For reducing overall file size, SwifDoo PDF adopts lossless compression, a technology used to identify and eliminate statistical redundancy. No information during compression is lost and the compression process only targets redundant data.



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In 160+ countries

Business & Home Users

Tips for Compressing PDF

How to Optimize the File Size with SwifDoo PDF

Open a PDF document withSwifDoo PDF
Click the “Advanced”button and select “Compression”
Choose the output fileformat and local folder before hitting the “Start”

FAQs about Compressing PDF

Q:Which is the best PDF compression app?

  • 1. PDF Compressor (online)
  • 2. iLovePDF (Windows, Mac, online)
  • 3. Adobe Acrobat (Windows, Mac)
  • 4. Soda PDF (Windows, Mac, online)
  • 5. Free PDF Compressor (Windows)
  • 6. Preview (Mac)
  • 7. SwifDoo PDF (Windows)

Q:Is it safe to compress PDFs online?

  • Generally speaking, it is safe to compress your PDF files online. Most of online service providers keep your files at their servers for 1 or two hours. When the time expires, your documents will be automatically deleted from their servers. However, for confidential files with sensitive information, it is not suggested to use online services.

Q:How do you resize a PDF file with Adobe Acrobat ?

  • 1. Launch Adobe Acrobat: clickon the "Optimize" button and then select the files you need to reducethe size;
  • 2. When you see many optionsat the top of the page, hit the "Reduce File Size";
  • 3. After a new window popsout, you are allowed to compress images, change their color settings, and setother options. Don't forget to tick the "Optimize images only if there isa reduction in size" - so that your images will not lost their quality.