Shrink PDF Files with Ghostscript

Compress and reduce the file size of a PDF using Ghostscript (gs). This optimizes documents for email attachments or web distribution.

Prerequisites

• Ghostscript (gs) installed on your system.

Command

Run the following command to compress <input.pdf> using the /ebook preset (150 dpi):

gs \
  -sDEVICE=pdfwrite \
  -dCompatibilityLevel=1.4 \
  -dPDFSETTINGS=/ebook \
  -dNOPAUSE \
  -dQUIET \
  -dBATCH \
  -sOutputFile=<output.pdf> \
  <input.pdf>

PDF Quality Presets

Adjust -dPDFSETTINGS to control resolution and output size:

• /screen: Lowest quality, smallest size (72 dpi).
• /ebook: Medium quality, balanced size (150 dpi, default recommendation).
• /printer: High quality (300 dpi).
• /prepress: Highest quality with full color preservation (300 dpi).

Verify

Compare the file sizes of the original and compressed documents:

ls -lh <input.pdf> <output.pdf>

Do not use the same filename for <sOutputFile> and <input.pdf>. Overwriting the input file directly can corrupt the PDF.