How to reduce a PDF’s file size

Updated

Email attachments and upload forms often stop at 10 or 20 MB. Most large PDFs are large because of pictures — scans and photos — so that is where the savings are.

Compress a PDF →

Steps

  1. Open Compress PDF and choose the file.
  2. Start with Lossless: it rewrites the file’s structure and keeps text selectable.
  3. Still too big? Balanced or Smallest turn pages into compressed images — ideal for scans you only need to read.
  4. Download and compare the size shown in the result.

Other ways to get under a limit

  • Split PDF sends a long document as two or three parts.
  • Remove pages nobody needs with Organise pages.
  • Scans made at 600 dpi are rarely needed; 200–300 dpi reads just as well.

Tools for this job

Compress PDF · Optimise for the web · Split PDF · PDF to images

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Black out sensitive passages — and remove them for good.

Compress PDF

Make the file smaller, with the trade-off you choose.

Repair PDF

Fix a damaged or corrupt PDF that will not open properly.