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3 Ways to Shrink PDF Size on Mac without Quality Loss

PDF file usually comes with lots of graphics and images, which may make PDF file size quite large. While, large PDFs often bring troubles when we send PDF by email but with a size limit, or eat up too much space on our mac. By this time, reducing PDF file size on mac becomes a crucial thing.

Here we offer 3 different ways to reduce PDF file size on mac, and without losing quality. You will find that solution to compress a pdf file on mac can be extremely easy.

The Most Efficient Way---Reduce PDF Size on Mac without Quality Loss

PDF users who work with PDF on a regular basis, prefer to choose an expert to do the compressing. We are all of the opinion that a professional program always offers the most efficient experience in compressing a single pdf or multiple PDFs, like Cisdem PDF Compressor for Mac. It is a powerful tool for users to shrink PDF file size on Mac with 100% success and first class compressing quality.

Follow the steps to reduce pdf file size on mac and retain original quality

  • Step 1. Download Free Trial of Cisdem PDF Compressor(Safe and Only 1.3MB)
  • Step 2. Drag and drop PDF files into the program
  • Step 3. Choose a compression mode (4modes available)
  • Step 4. Click “Compress” to start shrinking

Also, you can check the tutorial video of reducing pdf file size on mac:

What You Can Expect from Cisdem PDF Compressor

Tools to compress a pdf file on mac are plentiful enough, and choosing the best is really not easy. While, the reasons why Cisdem PDF Compressor comes as the best choice is not only due to its high quality compression, but also for a set of benefits it offers to users.

  • Reduce pdf file size with good quality---If you have higher requirement on shrinking PDF files on Mac, PDF Compressor Mac allows you to shrink PDF files in 4 modes, Minimal File Size, Small File Size, Medium File Size and Large File Size, even you can customize the quality by manually inputting the parameters. That's to say, if you choose Minimal Size Compression, a PDF file in 4.77MB also can be compressed to 45KB in good quality. And no matter how large your PDF is, this mac program can still offer a way to reduce the pdf file size on mac below 100kb.pdf compressor mac
  • Batch reduce---If you need to deal with many PDF files, this program makes it amazingly simple to reduce the size of one or multiple PDF files, which allow Mac users to import up to 50 PDF files at one time. batch convert
  • Shrink pdf file fast---The compressor processes compression extremely fast, within seconds, you will get files with reduced size. In my test, I compressed a 500-page PDF within 1 minute
  • Also work on protected PDF---Once you have input the correct password within this program, the compressor will continue to shrink your pdf file.word on protected pdf file

Compress Your PDF Files Now!

The Easiest Way---Shrink PDF on Mac with Adobe Acrobat

We all know, Adobe is leading in offering solutions to manage PDFs, its PDF editor, the Adobe Acrobat series is super powerful to handle all kinds of PDF files, including shrinking PDF on mac without quality loss.

Can Adobe Reader Reduce PDF File Size on mac?

One of my friends once asked me if Adobe Reader can reduce pdf file size on mac, the answer is NO.

Adobe Reader is a free PDF viewer open to everyone from Adobe, it allows users to view, highlight, add notes, print, fill and sign PDF. But if you need advanced features, such as editing, creating, exporting, compressing, etc., you will have to subscribe its Acrobat version.

Follow the steps to shrink PDF on Mac with good quality.

  1. Open the PDF that you want to shrink without quality loss with Adobe Acrobat Pro.
  2. Go to “File”-“Save As”-“Reduced Size PDF”-Finish. You will get a reduced PDF file with good quality.shrink pdf file size with adobe


  • High price
  • Incapability to batch shrink PDFs on mac.

The Most Affordable Way---Reduce PDF Size on Mac Online Free

Most online PDF compressors are free, which makes them the most affordable way to shrink a pdf. When it comes to online PDF compressor, the most popular is It is totally free. You can optimize your PDF by uploading it to the website or through email for compression. is browser-based and works for all platforms. It doesn’t matter if you use Mac, Windows or Linux.

However, Smallpdf also has some shortcomings. For example, you need to bear the advertisements on the screen, and you should pay attention to the risk you may meet, since online tool may bring risk of information leakage or invite spammers into your email box.

Neither does support batch PDF compression, and a default mode is set for users. For instance, a PDF file in 1.77MB will be compressed to 716.27KB.

Follow the steps to compress PDF on Mac Online Free

Step 1. At first, you need to click the hyperlink of to visit this site, be at ease, it is a safe link.

Step 2. Next, you should add your PDF file to Smallpdf. There are three ways for you to add PDF file, you can click “Choose File” to add, or just add by drag-n-drop, or you can add from Google Drive, Dropbox.

Shrink PDF on Mac with Smallpdf Step 1

Step 3. Online tool usually runs little slow, you need to be patient. Then you can click “Download File Now” to download your shrinked PDF file, or you can choose to save in your Google Drive or Dropbox.

Shrink PDF on Mac with Smallpdf Step 2


  • Batch compressing is not free
  • Potential risk of information leakage since your file is uploaded to the server for processing
  • Internet connection and file size will greatly impact the compressing

As there are lots of online free pdf compressors available, you may want to try others for a wiser decision. No need to do this yourself, we have done a review of several top online pdf compressor for your consideration.

Sometimes, A Mac is Enough

A Mac is designed to boost productivity both in life and work, so it is quite reasonable that some powerful applications comes with MacOS for totally free. Among these apps, there are 2 mac tools can reduce pdf file size on mac for free. One is Preview, while the other one is Colorsync.

Reduce PDF File Size on Mac Free with Preview

Preview is the free mac program developed to view and manage PDFs or images. With 3 steps, Preview can get your PDF file size reduced.

Step 1. Open PDF with Preview

Step 2. Go to File>Export>Quartz, choose “Reduce File Size”

Step 3. Click “Save”.
compress pdf mac preview

In my tests, I opened a 4.7-MB PDF in Preview and it finally compressed the file to be 121KB, and this file is filled with all images. It seemed that Preview could work perfect on reducing pdf file size in this case. But when I tried another file with a size of 4.3MB, which is mainly composed of text contents and several images, Preview finally brought me a file with 29.1MB, it even increased the file size! 


  • File quality is lost to some extent
  • Doesn't work on PDFs with complicate elements(images, texts, tables, etc.)
  • Cannot batch reduce pdf file size on mac

Compress PDF on Mac Free with ColorSync

Another mac tool to compress PDF is ColorSync, it is a color management system, helping users to modify an image by adding effect, tweaking color space, adjusting colors or brightness, etc.

Step 1. Go to Finder>Application folder, and open ColorSync Utility

Step 2. Go to File>Open, you will navigated top open PDF with ColorSync.

             colorsync open

Step 3. In the Filter menu, choose “Reduce File Size”, then click “Apply”.

colorsync reduce

Step 4. Go to File>Save as>Save.

In my tests, I successfully reduced a PDF file from 30.28MB to 128KB. However, ColorSync has the same issue as Preview. ColorSync manages to reduce pdf file size by compressing image files within the file, so it works when a PDF file mainly consist of images, but not work when you work on a quite normal PDF, let’s say, a PDF file consisting of different elements.


  • File quality can be easily sacrificed
  • Doesn't work on PDFs with complicate elements(images, texts, tables, etc.)
  • Doesn't support batch compressing

If these 2 solutions don't help, have a try on the best PDF Compressor for Mac.

Small Tips to Reduce PDF File Size on Mac

If you are not intended to reduce pdf file size with a software or online service, here are some small tips to compress pdf for you.

  1. Keep the image smaller: Very often, it is the images taking too much space. So, when you are working on PDFs, try to include an image in JPG format, which is in relatively smaller size.
  2. Delete unnecessary pages or images: Directly remove some pages or images (even multimedia objects) that are not necessary in your file. 
  3. Convert PDF to other formats: This really works when you are working on PDF image files or scanned PDF. I did this for several times, when I exported PDF in editable Word, or other formats, I did get a smaller PDF file.

Last Words on Compressing PDF on Mac

For Adobe Acrobat, if you are working on PDF files frequently, or you don't care about the high cost, it is a good choice. But, if you want a more efficient solution to shrink PDF on mac without quality scarified, without too much time and efforts consumed, a specialized software- Cisdem PDF Compressor won't let you down, give it a try now to shrink pdf file size on mac without losing quality!

2018-05-17 22:26:19 / Posted byMegan Charles to PDF Follow @ Megan

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1 Responses

  • Henry B

    I also got huge frustration from large size PDFs, I tried to compress in Adobe, but still too large to be viewed by our office software. Until I tried your method 2 and 3, and I personally recommend method 2, though you have to pay for it, it saves work.

    2 years ago REPLY

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