Shrink a scanned report for email
A 12 MB scanned PDF compressed at the High level often lands well under half its original size, since scans are usually saved at a far higher resolution than a screen or printer needs.
12.0 MB -> ~4.5 MBPDF Compressor
Drop a PDF, choose Low, Recommended, or High compression, and get a smaller file by recompressing its embedded images — compare the before-and-after size, then download.
AvailableIn Testing
Compression level
Or drop a PDF or choose a file.pdf · up to 40.0 MB. Sent to our server to process, then deleted right away.
Low keeps the most detail in scanned pages and photos. High shrinks the most by also reducing large images' resolution.
Drop a PDF, choose a compression level, then compress it on the processing server.
Results
Drop a PDF, choose a compression level, then compress it on the processing server.
This tool is still being fine-tuned, so you may run into the odd error. Spotted one? Let us know so we can fix it.
What is PDF Compressor?
Compress a PDF online by recompressing its embedded images and content streams, with Low, Recommended, and High levels, before-and-after size, and download.
How to compress a PDF
Shrink a PDF's file size by recompressing its embedded images, with three levels to balance quality against how much smaller the result gets.
How to use it
- Drop a PDF up to 40 MB.
- Choose a compression level: Low, Recommended, or High.
- Compress, then compare the original and new size.
- Download the compressed PDF.
What each level changes
Low re-encodes embedded images at a high JPEG quality without resizing them, keeping the most visual detail for the smallest guaranteed savings. Recommended balances quality and size, and also caps large images at 2000 pixels on their longest side. High goes further, using a lower JPEG quality and capping images at 1280 pixels, which shrinks photo-heavy or scanned PDFs the most.
What compression can and cannot do
- Most of a PDF's size usually comes from its embedded photos or scanned pages, so those get recompressed; text, fonts, and vector graphics are only losslessly restructured, not degraded.
- Small images such as icons and logos, transparent images, and black-and-white scanned pages are left untouched to avoid visible artifacts or a larger result.
- A PDF that is already efficiently compressed, or has no images at all, may shrink very little — the tool never returns a file larger than what you uploaded.
Compression level example
Processed temporarily on our server
The PDF is sent to a ProntoUso server because recompressing embedded images needs real PDF and image libraries a browser cannot run reliably on its own. It is processed only in memory for that one request and is never written to disk or kept afterward.
Frequently Asked Questions
Is my PDF uploaded?
Yes. It is sent to a ProntoUso server for compression, processed in memory only for that one request, and never stored or logged.
Will compressing reduce quality?
Recompressing embedded images is lossy at the Recommended and High levels, so some image detail is traded for a smaller file. Text, fonts, and vector graphics are never degraded.
Why didn't my PDF get much smaller?
PDFs that are mostly text, already have efficiently compressed images, or use images too small to recompress safely (icons, logos) have little left to shrink. The tool never returns a result larger than the original.
Can I compress a password-protected PDF?
Only if it opens with no password at all — many PDFs are flagged encrypted just to restrict printing or editing. Genuinely password-protected files are not supported.
What happens to scanned black-and-white pages?
Bilevel (black-and-white) scanned images are left at their original encoding, since re-encoding them as JPEG typically makes text scans both blurrier and larger.