Compress PDF — Reduce File Size Online
Shrink your PDF file size with adjustable compression quality. Everything happens in your browser — your files never leave your device.
Drag & Drop a PDF Here
or click to browse your files (single PDF)
How to Compress a PDF in 3 Simple Steps
Upload Your PDF
Drag and drop your PDF file into the upload area, or click to browse and select it from your device.
Choose Compression Level
Select Strong (-75%), Medium (recommended), or Basic (-30%) compression depending on your quality needs.
Compress & Download
Click Compress PDF. Your reduced-size file is generated instantly in your browser and downloaded to your device.
Why Use MyPDF to Compress PDF Files?
Unlike other online PDF compressors that upload your sensitive documents to remote servers, MyPDF's compression tool processes everything locally in your web browser. Your contracts, invoices, reports, and personal documents never leave your device. This makes it the safest option for reducing PDF file size for confidential information.
Whether you need to shrink a PDF for email attachment limits, reduce storage space, or speed up document sharing, MyPDF handles it instantly with adjustable quality levels and no watermarks. It works on any device — Windows, Mac, Linux, Chromebook, tablet, or phone.
Need more PDF tools? Try our PDF merger, PDF signing tool, or PDF password protector.
Frequently Asked Questions About PDF Compression
Is it safe to compress PDFs online?
Yes, with MyPDF it is completely safe. Unlike other online tools, your files are processed entirely in your browser using JavaScript. Nothing is uploaded to any server. Your documents stay on your device at all times.
How much can I reduce my PDF file size?
Depending on the compression level you choose, you can reduce file size by 30% to 75%. Strong compression gives the smallest file, Medium provides a good balance of size and quality, and Basic preserves the most detail with moderate reduction.
Will compression affect the quality of my PDF?
The compression works by re-rendering pages as optimized JPEG images at different quality scales. Strong compression noticeably reduces quality (best for text-heavy documents), Medium offers a good balance, and Basic maintains near-original quality with moderate size reduction.
Is there a file size limit for compression?
No artificial limits. Since processing happens in your browser, the only limitation is your device's available memory. Most PDFs up to 50MB compress without issues on modern devices.
Does this work on mobile devices?
Yes. The compression tool works on any device with a modern browser — iPhones, Android phones, iPads, tablets, and desktop computers. No app installation required.
