Compress PDF · 2 min read

How to Compress a Scanned PDF — Reduce File Size Without Losing Legibility

Scanned PDFs are often very large because they store full-resolution images of each page. Compressing them can reduce size by 60–90% while keeping text readable.

1

Why Scanned PDFs Are Large

Each scanned page is stored as a high-resolution image — often 200–400 DPI. For a 20-page scanned document, this can easily reach 20–50 MB.

2

Compress at pdfeditor.onl/compress-pdf

Upload the scanned PDF. Start with Good compression. Check the result — most scanned documents compress to 20–30% of their original size on Good settings while remaining clear at normal reading zoom.

Tip: For court filings or professional submissions, use Good compression and verify legibility at 100% zoom. Strong compression is fine for personal archives and emailing.

Compress Scanned PDF — Free →

Frequently Asked Questions

Will Strong compression make scanned text unreadable?

Strong compression reduces image resolution — text remains readable on screen at normal viewing sizes but may look slightly soft when zoomed in to 200%+. For professional submissions, test before sending.

Is this free?

Yes — completely free at pdfeditor.onl/compress-pdf.

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