5 Ways to Shrink a PDF
Practical ways to slim down heavy PDFs that keep running into email attachment and upload size limits.
Updated 2026-07-11 · 4 min read
Scanned documents and image-heavy PDFs can balloon to tens of megabytes, hitting email attachment limits and upload caps on submission sites. Here are the approaches that actually work.
1. Recompress the images
Most of a PDF's size is the images inside it. Re-encoding the pages as images at a sensible resolution cuts the size dramatically. That's exactly how OmniMindHub's PDF compressor works.
2. Keep only the pages you need
Simply dropping unused pages makes the file smaller. Use page extraction to turn just the range you need into a new PDF.
3. Scan at a lower resolution
Next time you scan, ask whether you really need 300dpi or more — 150–200dpi is plenty for a readable document. Making the file light from the start is the surest fix.
4. Be careful with text-based PDFs
TipRe-encoding a text PDF as images can actually make it bigger — and you lose text search and selection. Image recompression works best on scanned and photo-based PDFs.
5. Compress before you merge
If you're planning to merge several PDFs, compress each one first — the final result comes out lighter.
Make heavy PDFs lighter, right in the browser.
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