How to reduce pdf file size while exporting an InDesign file in to PDF

Go to Adobe PDF compressor website from Acrobat. It works wonderfully. https://www.adobe.com/ca/acrobat/online/compress-pdf.html
The question is why the online works better than the app??????
?????????

Hi guys,

I found that topic quite interesting, certainly because I was stuck with a PDF Print file that reached 2,4Gb and needed to be droped below 1Gb, because of a requirement from the Print house.

Not much of the above solutions worked enough for us and I guessed it'd be good to share what we experienced here.

The only things that really droped the size of our files are :

- Modifying the Graphics/ illustrtation by flattening the layers of the biggest psd files. That made them go from 500Mb to  about 40Mb. When such files are used in Masters in your ID document, it makes quite a difference.

- Without surprise, droping the DPI Compression from 300dpi to 250DPI. Minimum DPI for printing is 240 DPI so 250DPI was "ok".

- Using Adobe Acrobat and use the function "Save as other" + "Optimized PDF". Uncheck "Images" et check the rest (especially "Clean Up"). This has done quite some job as well. The issue there is that the application seems not to be able to handle big files and freezes at some point. To get arround it, I "just" split my Print PDFs in 3, optimized them, and assembled them back into one file via Adobe Acrobat's function "Merge files". 

- In the end, we got a new file just below 1Gb.

What knowledge did we get from this ?

- Adjusting the size of the PDF file is VERY time consuming.  Each export take several minutes, as well as each other step. Sometimes, the apps crash, making it quite frustrating. Just be prepared for some stress management especially if you are short in time.

- Layers in Graphics can be a problem. I would suggest make a copy and to flatten the images for Print purposes. 

- Transparency settings in ID is a real pain in the a##. It makes files size bloat in an impressive way. Moreover, once you've reached a certain point in size, Adobe Acrobat cannot flatten your file, nor optimize it. It just freezes, crashes down. One workaround would be to apply the opacity required in PS, not ID, and flatten it, getting a flat image to be put in place in ID.

- There is something more than just about graphics. The menu/ outcome from the "Optimized PDF" proves it. Maybe, for us, it was just about the "transparency" thing.

Hope it'll help people

Hi there! Here's what worked for me: My original PDF doc consisted of maaaaany pages that were very large, and I needed them downscaled to A4. The trick that finally worked best:
1) Open the pdf in Adobe Acrobat
2) Go to File --> Print --> Choose Printer "Adobe PDF"

3) Click "Properties", then go to tab "Adobe PDF Settings", then for the Adobe PDF Page size, select A4 (or whatever size you need. If you need a custom page size, you can click "add"). Click OK to go back to the Print dialog

4) In "Page Size and Handling" select whichever option makes your pages look best (I just did Shrink Oversize Pages for mine)

5) Print et voila!!! The new doc is the right size. Bit circuitous but ultimately quick and easy way to downsize many pages 🙂  This worked for me and saved so much time scaling tons of pages, hope it works for someone else!

Another thing I found that works which no one has mentioned yet is to change the PDF output type from Interactive to Print.  I found that the latter made the file about 1/3 the size.

I just had this problem with my design portfolio, which has a mix of rendered images and jpegs of architectural line drawings. 

I could not get it below 30MB without losing critical lineweights and overall image clarity, so I ended up exporting the pdf pages as JPEGs from Indesign, and then combining them in Acrobat and it ended up being 11MB (instead of 30MB) which I think is closer to a reasonable size. 

tldr: export as jpeg (from indesign), combine in Acrobat, done. 

Nice reply !! You can also use a free LightPDF tool to reduce PDF size. It never compromises my file quality.

To answer your specific question, you most effectively reduce PDF file size as follows when you export your PDF file from InDesign as follows:

(1) Choose export options that downsample images to lower resolutions. For example, the predefined print-oriented export options (i.e. .joboptions) downsample images to 300 dpi for images over 450 dpi. This is perfectly fine for PDF files being printed on high quality devices or that may be viewed on large 4K ultra high definition monitors. However, for less critical printing and/or viewing on lower resolution monitors, 150 dpi to 200 dpi may be adequate and could dramatically cut PDF file size.

(2) Choose export options that use lossier compression for raster images. Typically, the predefined export options use Automatic (JPEG) Maximum quality compression. Changing the Image Quality from Maximum to High or even Medium may yield acceptable results, but you should experiment.

(3) Combination of (1) and (2) above.

(4) Make sure to check the Compress Text and Line Art option. This option is non-lossy and can achieve significant compression for content that is not raster image-based.

(5) Check the Crop Image Data to Frames option. This option only includes the part of any images used by your InDesign document that actually are visible on output due to cropping within a frame. Note that this option can backfire on you if you repeat the same image multiple times in your document with different cropping.

If you properly export your PDF file and make prudent use of the points listed above, the tools available in Acrobat will be of minimal benefit to you in reducing your PDF file size with the least amount of lossiness.

Of course, if nothing really reduces the size of the PDF while maintaining adequate quality, you just might want or need to consider simplifying the content itself. Ultimately, you can't legislate a particular PDF file size without taking into account the overall quantity as well as quality of the content and the output!

          - Dov

In Acrobat, try Save as... Reduced size PDF or Optimized PDF.

How much you can gain from this, highly depends on the content of the file and your settings.

To reduce the size twice... why not, sometimes possible...