Compress PDF Online
Reduce PDF file size for email, forms, sharing and uploads while keeping good quality.
Compress PDF Online and Reduce File Size Easily
NeutronPDF helps you compress PDF files online in seconds. Reduce PDF size for email attachments, resumes, invoices, online forms, websites, document sharing, WhatsApp and cloud uploads. Choose the compression level that fits your needs, from stronger size reduction to higher visual quality.
This free PDF compressor is designed for students, job seekers, businesses, teams and everyday users who need smaller PDF files without a complicated workflow. Upload your file, choose a mode and download the optimized document directly in your browser.
Fast PDF compression
Upload your PDF, choose a compression level and download a smaller file in just a few clicks.
Works on all devices
Use this PDF compressor on desktop, tablet or mobile in all major modern browsers.
Multiple PDF support
Compress more than one PDF file in a single workflow and keep your documents organized.
How to compress a PDF file online
Compressing a PDF with NeutronPDF is simple. Upload your file, choose a compression mode and download the optimized version in moments.
Upload your PDF
Click Select PDF files or drag and drop your document into the upload area.
Choose a compression level
Select Extreme, Recommended or Less compression depending on whether you want smaller size or better quality.
Download the PDF
Start compression and download your optimized PDF file once processing is complete.
Why use an online PDF compressor
Smaller PDF files are easier to email, faster to upload and more convenient to store in cloud drives. If a document is too large for a job portal, business form, school application or customer submission, compressing the PDF can help you meet file size limits quickly.
NeutronPDF gives you flexible compression modes so you can prioritize either smaller file size or better visual quality depending on your document type.
Continue with more tools
Explore more tools to merge PDF files, convert PDF pages to images or turn images into a single PDF document.
Frequently asked questions
Find answers about PDF compression levels, file quality, supported devices, browser use and multiple file uploads.
Choose Recommended compression for the best balance between file size and document quality. Choose Extreme compression when you need the smallest possible PDF for email, uploads or messaging apps. Choose Less compression when readability, print quality and image clarity matter more.
Yes. You can upload multiple PDF files in one session. When several files are compressed together, NeutronPDF can prepare them as a ZIP download for easier saving, sharing and organization.
Compression can reduce visual quality depending on the mode you choose. Stronger compression usually creates smaller files by optimizing images and document resources more aggressively. If quality is more important than maximum reduction, use Less compression.
Yes. NeutronPDF works in modern browsers on Windows, macOS, Linux, iPhone, iPad and Android devices, so you can compress PDF files from desktop, tablet or mobile.
Some PDF files are already optimized or contain images and resources that are already compressed. In those cases, there may be only a small additional reduction in file size.
Yes. You can use the Compress PDF tool online for free directly in your browser without installing software.
Yes. Compressing a PDF is useful when you need a smaller file for email attachments, job applications, web uploads, school forms, business documents and cloud storage.
No. NeutronPDF is a browser-based PDF compressor, so you can reduce PDF size online without downloading desktop software.