Compress a PDF without uploading it
PDFs are exactly the files you shouldn't upload to a random converter site: contracts, invoices, ID scans, medical documents. This compressor never sees your file - your browser opens the PDF locally, redraws each page as an optimized image, and rebuilds the document on your device. Close the tab and nothing remains.
How to shrink a PDF
- Drop your PDF above.
- Pick a quality and resolution. For emailing scans, 96-120 DPI at 60-75% quality typically cuts the size by 70-90%.
- Click Compress PDF and download the result. The before/after size is shown so you can re-try with different settings instantly.
Why are scanned PDFs so huge?
Scanners often save pages as full-resolution, lightly-compressed images - a 10-page scan can easily be 50 MB. Re-encoding those pages at a sensible resolution and modern JPEG quality is exactly what this tool does, which is why the savings are usually dramatic.
What to expect from different kinds of PDF
PDF compression results vary enormously because PDFs vary enormously. A scanned document - where every page is secretly a large photograph - often shrinks by 60-90%, which is why a 40 MB scan can drop under 5 MB. A digitally created PDF full of text (an invoice, a contract exported from Word) is already efficient, and may only lose 10-30%. A presentation export stuffed with photos sits in between. If your result barely shrinks, that is usually the file telling you it was already compact, not the tool failing.
Limitations to know
Image-heavy compression is lossy: pushed hard enough, scanned text goes from crisp to fuzzy, so compress with the strongest setting that still reads cleanly rather than the strongest setting available - and keep the original. Password-protected PDFs must be unlocked before processing, and digitally signed PDFs will lose signature validity when modified, as with any editing tool. If the target size is still out of reach, splitting the document with the Split PDF tool and sending it in parts is often the practical answer.
FAQ
Does this PDF Compressor upload files to a server?
- No. The entire process - reading, rendering, rebuilding - happens in your browser.
Will the text still be readable?
- Yes, at the default settings text stays crisp. It won't be selectable/copyable in the compressed copy, because pages become optimized images.
Does it work with password-protected PDFs?
- Encrypted PDFs can't be opened without the password - remove protection first, then compress.
Is there a size limit?
- No fixed limit; very large PDFs are limited only by your device's memory.