Compress PDF
Reduce PDF file size while maintaining quality
Shrink your PDF file size for email, uploads, or archiving. Choose from four compression levels to balance quality and size. Server-side Ghostscript processing achieves stronger compression than browser-only methods.
How to use Compress PDF
Upload your PDF
Click the upload area or drag and drop your PDF. Files up to 50 MB are supported.
Choose a compression level
Select Screen (maximum compression), Ebook (balanced), Printer (high quality), or Prepress (archival quality).
Click Compress PDF
Your file is sent to the server, compressed with Ghostscript, and the result is sent back to your browser.
Download the compressed PDF
Review the file size reduction shown, then download your compressed PDF.
Drop a PDF here
or click to browse
Max 50 MB
What is PDF compression?
How small can a PDF get? That depends on what is inside it, and on the compressor doing the work. Compress PDF runs server-side Ghostscript, whose image-resampling pipeline reaches reductions that browser-only JavaScript compressors cannot match — which matters when a file has to clear an email gateway, a storage quota, or an upload cap.
Processing therefore happens on our server rather than in your browser tab. See our processing model for details on transport security and file-retention policy.
The limits that force compression are rarely negotiable. Gmail, Outlook, and Yahoo cap attachments at 25 MB; many government portals, university submission systems, and job application forms set the ceiling as low as 5 or 10 MB. Getting a 30 MB scan-heavy report down to 8 MB is the difference between a submission that goes through and one that bounces. Organisations archiving thousands of invoices, receipts, and contracts reclaim measurable storage by batch-compressing older material. For a walkthrough aimed specifically at email, see our guide on how to compress a PDF for email.
The four compression levels correspond to different Ghostscript output profiles. Screen (72 DPI) is the most aggressive and is suitable for on-screen viewing where images do not need to be sharp at print resolution. Ebook (150 DPI) strikes the best balance for most users, producing files that look good on screens and are acceptable for basic printing. Printer (300 DPI) preserves high image resolution for professional printing, and Prepress (300 DPI, color-preserving) is designed for commercial printing where color accuracy matters. Text content remains crisp at every level because compression only targets embedded raster images.
Frequently asked questions
How much will my PDF be compressed?
Compression results vary depending on content. PDFs heavy with high-resolution images typically compress by 50-80%. Text-heavy PDFs may only reduce by 10-30% since text is already very compact in PDF format. For very large PDFs, try splitting into smaller parts first, then compress each part individually.
Is it safe to upload my PDF for compression?
Yes. Files are processed on our server using Ghostscript and removed once the download is delivered. See our processing model for transport, retention, and logging specifics.
What is the maximum file size?
The maximum file size for PDF compression is 50 MB. If your PDF is larger, try splitting it first with the Split PDF tool, compressing each part, then merging the results.
Will compression affect the text or images in my PDF?
The compression level you choose controls the trade-off between file size and quality. Screen gives the smallest file but may reduce image resolution. Printer and Prepress preserve high quality at a larger size. Text content is never visually degraded.
How do I compress a PDF for email?
Upload your PDF, select the Ebook compression level for a good balance of size and quality, and click Compress. Most email services allow attachments up to 25 MB. If your compressed PDF is still too large, try the Screen level for maximum compression, or split the PDF into smaller parts and send them separately.
Can I compress a scanned PDF without losing readability?
Yes. Scanned PDFs are essentially images embedded in a PDF wrapper, so they respond very well to compression. The Ebook level (150 DPI) typically reduces scanned documents by 50-70% while keeping text fully legible on screen. If the document will be reprinted at full size, use the Printer level instead to maintain 300 DPI clarity.
Why is my compressed PDF larger than the original?
This can happen with PDFs that are already well-optimized or contain mostly vector graphics and text. Ghostscript may re-encode the internal stream structures in a way that marginally increases size. If the compressed file is not meaningfully smaller, the original was likely already near-optimal and does not benefit from further compression.
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