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Compress PDF

Reduce PDF file size by recompressing images and optimizing structure.

Drop your file here

.pdf

Savings depend on the content; text-only PDFs shrink less than image-heavy ones.

How to use Compress PDF

  1. 1

    Choose a file (.pdf) or drop it into the box.

  2. 2

    Adjust the options to suit your needs.

  3. 3

    Click “Compress PDF” and download the result: smaller pdf.

Your documents are processed entirely inside your browser. They are never uploaded to PDF100 or any third party, so Compress PDF is suitable for confidential files. Read our privacy policy.

About Compress PDF

Compress PDF makes a PDF smaller by recompressing the images inside it and cleaning up the file structure. Choose Low to keep the best quality, Recommended for a balance, or Strong when the smallest possible file matters most.

How much you save depends on the document. Scans and photo-heavy PDFs usually shrink the most, while text-only files are often small already and change less.

When to use it

  • Getting a PDF under an email attachment limit
  • Meeting the upload size limit on job, visa or university application portals
  • Shrinking scanned documents taken with a phone before sharing them
  • Saving storage space when archiving large reports

Tips for better results

  • Start with Recommended and only switch to Strong if the file is still too large.
  • Check small text and signatures after Strong compression, because images are reduced the most at that level.
  • If a file is still too big, use Split PDF to send it in several parts.
  • Removing pages you do not need (Remove pages) also cuts the file size.

Compress PDF questions

Why did my PDF barely get smaller?

Text-only PDFs and files that are already optimized have little left to compress. The biggest savings come from PDFs that contain large photos or scans.

Will compression make my text blurry?

Real text in a PDF stays sharp because it is not an image. Only embedded images are recompressed, and the Low setting keeps them closest to the original.

Is Compress PDF free?

Yes. Compress PDF on PDF100 is free with no account, no watermark and no daily limit. The site is supported by advertising.

Are my files uploaded when I use Compress PDF?

No. Compress PDF runs entirely inside your browser tab. The file is read and processed on your device and the result is saved straight to your downloads, so no copy reaches our servers.

Which files does Compress PDF accept?

Compress PDF accepts .pdf. The result is: smaller pdf.

Is there a file size limit?

There is no fixed limit set by PDF100. Because processing happens on your device, the practical limit is your browser memory. Very large files work best on a desktop computer.

Does Compress PDF work on my phone?

Yes. Compress PDF works in current versions of Chrome, Safari, Edge and Firefox on desktop and mobile. Large documents are faster on a computer.

Are there any limitations?

Savings depend on the content; text-only PDFs shrink less than image-heavy ones.

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