One can use Preview to compress a PDF. However Preview on Mac OS X 10.7 does a too hard compression for my taste. There is only one compression setting.
Are there alternative tools that allows you to adjust the compression ratio?
As Guy mentioned, ColorSync Utility is what your looking for. For me the standard compression was also too little resolution & too lossy compression. So I created a new filter in ColorSync - which then becomes available in e.g. Preview: Resolution 200 dpi, jpeg quality ~75%
Step 1: Open ColorSync Utility & create the new filter such as below
The above settings give me files with acceptable size and decent quality (e.g. for sending by e-mail)
Step 2: Open the PDF in Preview, then choose File > Export, Click the Quartz Filter pop-up menu, then choose the relevant filter ("Reduce File Size 200dpi" in this case)
Edit 2011-12-18: Seems for Lion it's not that straight forward regarding Preview integration. See here:
Just copy your filter from /Users/YourName/Library/Filters/ to /Library/PDF Services/ and the customized profile will be back in preview.
Ahhh! Turns out that you can fine tune the quartz filter that Preview uses. This might be a faster way to compress:
This is from a review of PDFCompress on Macupdate.com:
With Quartz Filters, you can take total control of the compression process. In Leopard (perhaps Tiger or earlier, I'm don't recall), in your Utilities folder you'll find "ColorSync Utility". With this program, you can create you own quartz filters which allow to you compress PDFs as much as you see fit. When you start ColorSync Utility, you'll see how Apple programmed their "Reduce File Size" quartz filter that you see in Preview. It's remarkably easy to make your own filter by modeling it off Apple's filter. Head on over to for a quick tutorial. Also, some nice guy on Apple's Discussion boards put up a bunch of premade filters you can download that do the same thing. A follow-up poster even posted AppleScript code and Automator recommendations to make compressing PDFs a snap! Check out for more on that. Happy PDF-Shrinking!
I have used PDFCompress for years. It offers multiple options and hs been continuously updated. Highly recommended, but now $30. There may be cheaper options, but this has worked well for me.
To compress a PDF using some settings, you can use PDF Toolkit+. It used to be $2, but it's currently free. It does not allow adjustable ratio, but has specific settings of 150 or 72 dpi.
To compress a PDF using some settings, you can use PDFOptim - http://rootrisetech.com/product/pdfoptim