Compress PDF file
Reduce file size while optimizing for maximal PDF quality.
Compress PDF Online — Reduce File Size Without Losing Quality
NeutronPDF helps you compress PDF files online in seconds. Choose a compression level based on your needs—smaller size for faster sharing, or higher quality for printing and official documents. This tool works globally (USA, UK, Canada, Europe and more) on any device including Windows, macOS, iPhone, Android and Linux.
How to compress a PDF
- Click Select PDF files or drag and drop your PDF.
- Choose a compression level: Extreme, Recommended, or Less.
- Click Compress PDF to download your optimized file.
Frequently asked questions
Which compression level should I choose?
Use Recommended for best balance, Extreme for the smallest size, and Less when you want the highest quality.
Can I compress multiple PDFs at once?
Yes. Upload multiple PDFs and NeutronPDF will return a ZIP download.
Will compression reduce quality?
Compression may reduce quality depending on the level chosen. Use Less to keep quality as high as possible.
Does this work on iPhone, Mac, and Windows?
Yes—NeutronPDF works in modern browsers across all major devices and operating systems.
Why does a small PDF sometimes not compress further?
If a PDF is already optimized (low-res images / compressed streams), it may not shrink much. In those cases, different methods can give different results.