Free · local browser tool
Compress PDFs locally, with honest tradeoffs.
Reduce PDF size without sending the document to a remote server. Choose structure cleanup for text-based files or image re-encoding for scans when a smaller file matters more than preserving the text layer.
Free tools need no account within the standard limits of 20 MB and 100 pages. Larger files require eligible Pro access and are subject to device capacity. Beta rules · Plans and limits
How to use Compress PDF
- 01Open a PDF in the workspace
- 02Choose automatic, structure, or image mode
- 03Download only when the result is smaller
Why PDFbuff
A direct path from file to result.
Local browser compression
Text-preserving structure mode
Stronger image mode for scans
Adjustable image quality
Know the boundary
What this tool does—and what it does not.
Compression is not guaranteed. Image re-encoding can remove searchable text, forms, annotations, and other PDF structure, so use it only when that tradeoff is acceptable.
Compress PDF FAQ
Before you start.
Will every PDF become smaller?
No. Already optimized PDFs may stay the same size or become larger, and PDFbuff will not download a candidate that is not smaller.
Which mode should I use?
Use structure mode for text-based PDFs. Use image re-encoding only for scanned or image-heavy PDFs when losing the text layer is acceptable.
Does PDFbuff upload the file to compress it?
No. Compression runs in your browser.
Can compression affect quality?
Structure mode aims to preserve content. Image mode trades visual quality and PDF structure for a potentially smaller file.
Ready when you are