Compress PDF: Reduce PDF File Size Free Online

Make PDFs up to 99% smaller and compare before and after.

Choose PDF files

or drop PDFs here · up to 20 files

Compress PDF makes your PDF smaller so it is easy to email and upload. As soon as you add a file, it is compressed at three levels and you see the real new size of each one. Drag the before and after line and zoom in to check the quality, then download. Text and drawings stay sharp; only photos and scans are resized to the resolution they are shown at.

How to compress a PDF

  1. Click "Choose PDF files" or drag and drop up to 20 PDFs into the box.
  2. Wait a moment: Light, Recommended and Strong each show the real new size.
  3. Pick a level, or choose Custom to set the resolution (DPI) and image quality yourself.
  4. Drag the before and after line and zoom in to check the pages.
  5. Click "Download PDF" (or "Download all" as a ZIP for many files).

Why use ZentaPDF Compress PDF?

Easy to useSimple steps, clear buttons — done in a few clicks.
Free, no sign-upNo account, no email, no watermark and no daily limits.
FastNo waiting — results are ready in seconds.
Works everywhereUse it on Windows, Mac, Linux, Android or iPhone in any modern browser.
Original qualityPages are copied as they are — text and images stay crisp.
Large filesHandle big files and many pages — limited only by your device’s memory.

Frequently asked questions

How much smaller will my PDF get?

PDFs with photos, scans or designs from apps like Canva often shrink by 80 to 99%. PDFs that are mostly text are usually small already and shrink less.

Will the text get blurry?

No. Text, lines and vector drawings are not changed. Only pictures are resized to the resolution they are shown at on the page, and you can check this with the before and after view.

What is the difference between the levels?

Light keeps pictures at 220 DPI for printing, Recommended uses 150 DPI which looks sharp on screens and is ideal for email, and Strong uses 96 DPI for the smallest file. Custom lets you choose the DPI and quality yourself.

Can I compress many PDFs at once?

Yes. Add up to 20 PDFs; each one shows its own result, and you can download them one by one or all together as a ZIP file.

My PDF is locked. Can I still compress it?

If the PDF opens without a password but is locked against editing, it is compressed normally. If it needs a password to open, unlock it first with our Unlock PDF tool.

Is it really free? Do you add a watermark?

Yes, it is completely free with no sign-up, no watermark and no daily limits. The site is supported by a few non-intrusive ads.

Guides

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