Start with Light
Light compression preserves document structure, selectable text, vector graphics, links, and forms where the PDF library can retain them.
PDF Tools · Local processing
Compress PDF
Measure real PDF size reduction locally, with a structure-preserving option and clearly disclosed flattening modes.
Measured local PDF compression
Compress a PDF with an honest quality tradeoff
The practical guide
Choose compression based on what the document must preserve.
Light mode rewrites the PDF structure without promising large savings. Balanced and Strong can reduce scanned PDFs more aggressively by rebuilding each page as an image.
Flatten only deliberately
Balanced and Strong are useful for scans, but page rasterization removes interactive and structural PDF features. The tool requires an explicit confirmation.
Trust measured results
Original and output sizes are compared only after processing. Some already optimized PDFs will not become smaller.
Privacy by architecture
Your files and tool inputs stay in your browser.
The selected files, inputs, settings, and outputs are processed in this page and are not uploaded to any server.
Questions, answered
Frequently asked questions
Is my PDF uploaded?
No. The PDF is read, rendered when requested, rebuilt, and downloaded within this browser.
Why can't every PDF be compressed significantly?
Many PDFs already use compressed image and object streams. Re-saving those files may produce little or no reduction.
Will text remain selectable?
Light mode aims to preserve selectable text. Balanced and Strong flatten pages, so text becomes part of an image.
Can I compress scanned PDFs?
Yes. Scanned PDFs are often the best candidates for the explicitly flattened Balanced or Strong modes.