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Compress PDF

Make a PDF small enough for an email attachment or a portal's size limit. Choose a level, compare the before and after size, and keep whichever version suits you.

What is a PDF compressor?

A PDF compressor reduces a PDF's file size so it fits email attachment limits and the 1 MB or 2 MB caps common on job, exam and government portals. Most of the bulk in large PDFs comes from scanned pages and photos stored at higher resolution than anyone needs on screen.

This compressor offers a lossless option that tidies the file without changing what you see, and three image levels that redraw every page at 150, 110 or 80 DPI as JPEG. It shows the original size, the new size and the percentage saved, and tells you plainly when a level didn't help. The file is processed on your device.

How to use the Compress PDF

  1. 1.Choose a PDF

    Up to 200 MB. Scanned documents and photo-heavy PDFs shrink the most.

  2. 2.Pick a level

    Lossless for documents you need to edit or search; Balanced, Small or Smallest for scans.

  3. 3.Compress and compare

    See the new size and the saving, then download. If it didn't get smaller, try a stronger level.

Example: what Balanced does to one A4 page

Each page of a scanned A4 PDF at the Balanced level:

Page size
595.28 × 841.89 pt (A4)
Redrawn at
150 DPI = 1240 × 1753 px
Saved as
JPEG at 70% quality
A 300 DPI scan of the same page
2480 × 3507 px, four times the pixels

Dropping a 300 DPI scan to 150 DPI keeps a quarter of the pixels, and 70% JPEG quality shrinks each page further. Actual savings depend on how the original was saved.

Lossless or image levels?

Lossless repacks the PDF's internal structure and drops unused objects, leaving text, fonts and images untouched. It helps most with files saved by older software, and may do little on PDFs that are already efficient.

The image levels redraw each page as a JPEG picture at a lower resolution, which is what shrinks scans of 5–20 MB down to a few hundred KB. The catch is that the text in the result becomes part of the picture: it can't be selected, searched or edited, and links stop working. That's fine for scanned certificates and ID proofs, which were pictures already.

Frequently asked questions

How do I get a PDF under 1 MB or 2 MB?

Start with Balanced. If it's still too big, try Small, then Smallest. A 10-page scan at Small usually lands around 0.5–1.5 MB.

Why did my PDF get bigger?

Text-only PDFs are already tiny, and turning their pages into images adds size. Use Lossless for those, or keep the original.

Will the compressed PDF be blurry?

Balanced looks sharp on screens. Smallest can make small print fuzzy, so zoom in to check before you send it.

Is my document uploaded to a server?

No. Pages are drawn and re-saved inside your browser.

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