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Compress PDF – Reduce PDF File Size for Email and Upload Forms

Make a large PDF small enough to email or to upload to a job, visa or exam portal. Choose how strongly to compress, optionally switch to black and white, and see the size before and after. The PDF is processed on your own device and never uploaded.

Your files stay on your device

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How to compress a PDF

  1. Choose your PDF. You’ll see its current size and number of pages.
  2. Pick a compression level: Light, Recommended or Strong.
  3. Tick Black and white for documents where colour doesn’t matter — it saves more.
  4. Press Compress PDF and wait while each page is processed.
  5. Check the new size and press Download PDF.

Compression levels

LevelResolutionJPEG qualityBest for
Light150 DPIHighDocuments you may print
Recommended110 DPIMediumEmail and most upload forms
Strong80 DPILowerStrict size limits

DPI (dots per inch) is how many pixels are used for each inch of the page. A typical computer screen shows about 100 DPI, so 110 DPI still looks sharp on screen.

What shrinks well — and what doesn’t

Shrinks a lot:

  • Scans from a phone or office scanner, which are often saved at 300 DPI or more.
  • PDFs full of photos, such as brochures and portfolios.
  • Documents exported with high-resolution images.

Doesn’t shrink (may grow):

  • Text-only PDFs exported from Word or Google Docs — they’re already tiny.
  • Forms with lots of fillable fields and vector graphics.

Example

A 12-page scanned contract saved at 300 DPI might be about 9 MB. At Recommended compression it typically drops to around 1–2 MB, and with black and white often below 1 MB — small enough for most email attachments and upload portals. Results vary with the scan.

Tips for strict upload limits

  • Remove pages you don’t need with split PDF or organize PDF.
  • Use black and white for text documents.
  • Scan at 150–200 DPI in future instead of 300–600 DPI.
  • Split into parts if the portal accepts several files.
  • Check the result by zooming in before you submit — small text should still be readable.

Checking the result

After compressing, open the new PDF and zoom in on the smallest text, signatures and stamps. If anything is hard to read, go back and choose a lighter level. Upload portals usually reject unreadable documents, so a slightly larger file that passes is better than a tiny one that doesn’t.

Privacy

Many online compressors upload your PDF to a server. Here, compression happens with your browser’s own PDF engine, so passports, bank statements and contracts stay on your device.

To combine several files first, use merge PDF. For photos, the image compressor can hit an exact size in KB before you turn them into a PDF with JPG to PDF.

Frequently asked questions

How does PDF compression work here?

Each page is redrawn as a compressed image at a lower resolution, and the images are put into a new PDF at the original page size. Scanned documents and photo-heavy PDFs usually shrink a lot.

Will the text still be selectable?

No. Because pages become images, you can no longer select, copy or search the text. Keep your original file if you need those features, and use the compressed copy for uploading or emailing.

Which compression level should I choose?

Start with Recommended (110 DPI), which keeps documents readable on screen and when printed. Use Strong (80 DPI) when a portal has a strict limit, and Light (150 DPI) when quality matters most.

Why is my compressed PDF bigger?

PDFs that are mostly text are already very small, because text is stored as characters rather than pictures. Turning those pages into images can make the file larger. The tool tells you when that happens so you can keep the original.

How do I get a PDF under 1 MB or 200 KB?

Try Strong compression, and tick black and white for documents without colour. For very strict limits, split the PDF into parts with the split tool or remove pages you don’t need.

Is it safe for confidential documents?

Yes. The file is read and compressed in your browser — it is not uploaded to any server.

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