Compress a PDF. Losslessly, without uploading it
This is a lossless optimizer. It uses qpdf compiled to WebAssembly to restructure object streams and recompress internal data without changing text, images, or fonts. Savings are typically 5–30% for PDFs created by office software with inefficient internal structure. PDFs made mostly of scanned images may barely shrink because reducing those images would require lossy recompression. The page shows input and output sizes side by side, and the document remains on your device.
How it works
- Drop a PDF below or click to choose one.
- qpdf rewrites the file structure losslessly. Content and quality are untouched.
- Compare the input and output sizes shown, then download name-optimized.pdf.
Frequently asked questions
How much smaller will my PDF actually get?
Typically 5–30%, although some files show almost no change. Restructured object streams, recompressed metadata, and removed unused space help PDFs from word processors and report generators most. Scanned PDFs shrink less because this tool does not recompress their images.
Will the compressed PDF look any different?
No. That is the guarantee of lossless optimization. Every character, image, and vector shape is preserved exactly; only the file’s internal plumbing is reorganized. If another tool promises dramatic shrinkage of scanned PDFs, it is downsampling your images. This one never does.
Is my PDF uploaded for compression?
No. qpdf is compiled to WebAssembly and executes inside your browser, the same way it would run on your own command line. Financial statements, contracts, and medical documents are processed entirely in local memory. No server, no upload, and it works offline once the page has loaded.
What is qpdf?
qpdf is a mature, widely used open-source command-line tool for structural PDF transformations. The kind of software packaged in every major Linux distribution. Here it runs as WebAssembly in your browser tab, which means you get a trusted, battle-tested optimizer without installing anything or sending your file anywhere.