Compress a PDF and reduce its file size
Make large PDFs small enough to email or upload. Choose how much to compress, see the size before and after, and keep your original in case you need full quality.
Free plan with no time limit. Pro free for 7 days, no card needed.
How to compress a PDF
Choose the PDF
Pick a document from your library or upload it, and open Compress PDF.
Pick a quality level
Best quality, Balanced (recommended) or Smallest file, from pictures that stay sharp to the smallest possible size.
Compare and download
See the size before and after. The smaller PDF is saved as a new version, and the full-quality original stays in its history.
Smaller files, readable pages
Three quality levels
Balance size and quality for printing, sharing on screen or squeezing under an email limit.
Size before and after
See how much smaller the file is before you download it.
Pictures resized smartly
Pictures are resized and re-compressed, which is where most of a PDF's size usually comes from.
Optimize for the web
Need a PDF that opens fast online? Optimize for web shows the first page while the rest downloads.
Many files at once
Compress up to 20 documents in one go. If a file can't be made any smaller, it's left as it is.
Private by design
Encrypted and private
Every file is encrypted before it's stored, and only you and the people you share with can open it.
Your original stays safe
Every change is saved as a new version. The original is never changed, and you can restore it at any time.
No watermarks
Files you save never get a watermark, on any plan, including the free one.
Works in your browser
Nothing to install. Use it on Windows, Mac, Linux, Chromebooks, iPhone, iPad and Android.
Questions and answers
How do I reduce the size of a PDF?
Open Compress PDF in PDFZyro, choose the document and a quality level, and download the smaller file. Most of the savings come from resizing and re-compressing pictures.
Will compressing a PDF lower its quality?
Text stays sharp. Pictures may lose some detail, more at the strongest level. Try the lighter level first if the document has photos you need to keep crisp.
Why is my PDF still large after compressing?
PDFs that are mostly text are often already small, and some contain many fonts or pages. Splitting the document can help if you only need some pages.
Does compressing replace my original?
No. The compressed PDF is saved as a new version of the document, and the original stays in its history, so you can always go back to full quality.
Is Compress PDF free?
Yes. The Free plan includes 3 edit, convert, compress or OCR tasks a day, with files up to 50 MB, and never adds a watermark. Pro removes the daily limit and is free to try for 7 days, with no card needed.
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