Compress a PDF to 25MB (macOS)
This guide shows how to shrink large scanned PDFs to 25MB for strict upload limits. SecureCompress focuses on local processing and precise target sizes.
Author
Written by the SecureCompress team. Our experience comes from building local-first utilities for large scanned documents and strict upload portals.
Step-by-step
1. Download & install
Get the macOS app and drag it into Applications.
2. Set a target
Drop your PDF and set 25MB (or your required limit).
3. Review output
Check small text and re-run with a slightly larger target if needed.
Case study: 800MB scan → 25MB
Input
812MB, 420 pages, color scans.
Settings
Target 25MB, grayscale, 200 DPI, 2 passes.
Result
26.1MB on first pass, 24.8MB after adjustment.
SecureCompress vs online tools
Privacy
Local processing keeps sensitive documents offline.
Target control
Dial in exact limits for university or government portals.
Repeatable results
Reuse the same settings across batches of scans.
DPI & mode guidance
200 DPI (default)
Balanced clarity for most scans.
Grayscale
Best for text-heavy PDFs and small fonts.
Black & white
Use for line art when size is critical.
Tips for scanned PDFs
- •Use grayscale for text-heavy scans
- •Avoid extreme compression ratios when readability matters
- •If the output is still too large, lower the target and increase passes