A scanned PDF's file size is set by its DPI - dots per inch on each page. At 300 DPI, one colour page is about 1.2 MB; at 150 DPI greyscale, the same page drops to roughly 150 KB. At 96 DPI, that page falls below 100 KB, but text edges start to blur.
GekiPDF's compress tool rewrites your scan using Ghostscript presets: Light (~200 DPI), Recommended (~150 DPI), or Extreme (~96-120 DPI). It keeps the text layer and drops metadata. A 16-page scan takes about 1 second, and files are deleted after one hour.
Frequently asked questions
What does DPI mean in a scanned PDF?
DPI means dots per inch, or pixel density of each page image. Higher DPI = more detail and larger file. Lower DPI = smaller file but softer text.
Which DPI should I choose for emailing a scan?
Use Recommended (~150 DPI). It cuts file size by over 80% while keeping most text legible. For forms with small print, try Light instead.
Does compressing change the words in my PDF?
No, GekiPDF keeps the existing text layer intact. It only downsamples the background images, so searchable text stays unchanged.
Do it in the full tool
Open Compress PDF for all options, or jump straight to another step below.
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