Elevatools
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PDF compression: how it works and when to use it

Why your 30MB PDF becomes 3MB without losing readability.

Elevatools Team·2026-01-15· 3 min
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What gets compressed

  • Images inside the PDF (lossy JPEG re-encoding).
  • Fonts (subsetting).
  • Streams (deflate / lzw).

Three quality tiers

  • High — for printing (200–300 DPI images).
  • Medium — for screen (150 DPI).
  • Low — for email (75 DPI).

When NOT to compress

  • Legal documents that must be archival-quality.
  • Anything signed digitally (compression invalidates signatures unless re-signed).

How to compress

Elevatools PDF Tools (coming soon) compress in-browser — your file never leaves your device.