PDF Compressor
Upload a PDF and download a compressed version. We re-save your file with object-stream optimization to reduce size—typically 15–25% for document-heavy PDFs. No signup required for the first 5 pages.
A free PDF compressor lets you reduce PDF file size without losing quality or buying desktop software. Whether you need to shrink a PDF for email, save storage, or meet upload limits, our online tool uses object-stream optimization to make your document smaller. Document-heavy PDFs (text, vector graphics, form fields) typically see 15–25% size reduction. The process is non-destructive: we re-encode the PDF structure rather than downscaling images or removing content, so your text and layout stay sharp. No signup is required for the first 5 pages—upload, compress, and download in seconds. For full-document and bulk PDF compression, sign up for a free account or try our Bulk PDF Compressor.
Why Use Our PDF Compressor?
Fast, private compression that preserves quality—no desktop install required.
Object-Stream Optimization
We re-save your PDF with object streams enabled, which compresses repeated objects and stream data. This reduces file size without changing how the document looks or prints.
Private & Secure
Your PDF is processed in memory and never stored. We don’t keep copies or log file contents. Compression happens on our servers over encrypted connections.
Instant Download
Upload, compress, and download in seconds. No account needed for the first 5 pages. For larger documents or batch compression, sign up for free API and bulk tools.
How It Works
Compress your PDF in two simple steps. We use object-stream optimization so your content and quality stay the same—only the file size shrinks.
Upload PDF
Drag and drop your PDF or click to browse. We support any standard PDF up to 50MB. The first 5 pages are free without an account; sign in for full-document compression.
Download Compressed PDF
We re-save your file with object streams enabled. You get a smaller PDF to download immediately. Text, images, and layout are preserved—no visual quality loss.
How We Compare
See how DocLD’s PDF compressor stacks up against other options for reducing PDF file size.
| Feature | DocLD | Adobe Acrobat | Free Online Tools |
|---|---|---|---|
| Reduce PDF size | |||
| No quality loss (object-stream) | |||
| Privacy (no storage) | |||
| Free tier | 5 pages free | Limited | |
| No sign-up required | |||
| API / bulk |
Popular Use Cases
Reduce PDF file size for email, storage, and upload limits across industries.
Email attachments
Shrink PDFs to stay under email size limits while keeping content and readability intact.
Portals & uploads
Meet strict file-size limits on job applications, grants, or document portals without losing quality.
Storage & backup
Compress large PDF archives to save disk space and speed up backups and transfers.
Legal & contracts
Reduce contract and filing PDF sizes for secure sharing and e-signature platforms.
Reports & presentations
Make reports and slide-deck PDFs smaller for faster distribution and viewing.
Web & mobile
Optimize PDFs for web and app delivery so they load faster on slow connections.
How PDF Compression Works
PDFs can be made smaller in two main ways: by re-encoding internal structure (lossless) or by reducing image resolution (lossy). Our free PDF compressor uses object-stream optimization only. That means we enable PDF object streams so repeated objects and stream data are compressed—similar to turning on “compress object streams” in Acrobat. Your text, vector graphics, and images are not resampled or downscaled, so there is no loss of visual quality. You typically see 15–25% size reduction on document-heavy PDFs (forms, reports, text-heavy files). Image-heavy PDFs (scans, photos) may see smaller gains; for those, tools that downscale images can reduce size further but will reduce image quality. For a balance of size and quality without any loss, our compressor is ideal.
If you need to compress many PDFs at once, use our Bulk PDF Compressor to process multiple files and download a single ZIP. Signed-in users get access to API and higher limits.
Tips for Best Results
Get the most out of PDF compression with these simple tips.
Best for text-heavy PDFs
Documents with lots of text and vector graphics see the largest size reduction (often 15–25%).
Image-heavy PDFs
Scanned PDFs or photo-heavy files may see smaller gains; object streams still help without any quality loss.
Already optimized PDFs
If your PDF was already saved with object streams, size change may be minimal—the file is already efficient.
Files are not stored
We process your PDF in memory and do not keep copies. Download the compressed file and close the tab when done.
Frequently Asked Questions
Need more document tools?
Sign up for free to unlock API access, full-document compression, and batch processing. Or explore more free tools—view all tools.