GekiPDF

Why Scanned PDFs Are Large (and How to Shrink Them)

Scanned PDFs are large because each page is a bitmap. At 300 DPI, one colour page can be 1.2 MB. Use GekiPDF's compress tool to reduce size.

    Runs the same engine as our Compress PDF tool.

    A scanned PDF file is large because every page is stored as an image, not as text. A single 300 DPI colour page can take about 1.2 MB of space. If you scan a 16-page document at that resolution, you get roughly 19 MB before any compression – too big for most email attachments.

    GekiPDF's compress-pdf tool rewrites the file and downsamples those images. Choose Light (~200 DPI) for near-original quality, Recommended (~150 DPI) to cut size by up to 95%, or Extreme (~96-120 DPI) for the smallest file. It takes about 1 second per 16 pages, keeps the text layer, and drops metadata.

    Frequently asked questions

    What makes scanned PDFs so much larger than normal PDFs?

    Normal PDFs store text as characters, which are tiny. Scanned pages are full-resolution bitmaps – each pixel adds data. At 300 DPI, a single page can be over 1 MB.

    How much smaller will my scanned PDF get with GekiPDF?

    At Recommended preset (150 DPI), a typical scan shrinks by up to 90-95%. For example, a 32 MB scan often drops to around 1.5 MB, depending on content.

    Will I lose the ability to search or select text after compressing?

    No. The compress tool keeps the existing text layer if your scan already has one. It only downsamples the background images, so text remains selectable.

    Do it in the full tool

    Open Compress PDF for all options, or jump straight to another step below.

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