Compressing PDF Files using MacOS or Linux

The method I’m using requires ghostscript. Ghostscript is a high quality, high performance Postscript and PDF interpreter and rendering engine.

If you’re using a Mac, you can install ghostscript using brew:

brew install ghostscript

If you’re using Linux you can install ghostscript from aptitude, or your package manager of choice.

Now, you can use ghostscript to compress your PDF file for the web:

gs -sDEVICE=pdfwrite -dNOPAUSE -dQUIET -dBATCH -dPDFSETTINGS=/screen -dCompatibilityLevel=1.4 -sOutputFile=output.pdf input.pdf

That’s not exactly a memorable command, so I’ve made a function that you can add to your ~/.bash_profile to allow you to easily compress PDF files from your terminal:

# Usage: compresspdf [input file] [output file] [screen*|ebook|printer|prepress]
compresspdf() {
    gs -sDEVICE=pdfwrite -dNOPAUSE -dQUIET -dBATCH -dPDFSETTINGS=/${3:-"screen"} -dCompatibilityLevel=1.4 -sOutputFile="$2" "$1"
}

Now you can simply run the following command:

compresspdf "Massive.pdf" "Small.pdf"

Using this command I managed to compress an A3 size PDF (originally around 9MB) down to just under 1MB, which is perfect for the web.