Compress PDF
Shrink a PDF's file size, losslessly.
Free PDF compressor. Upload a PDF and rebuild it with object streams to trim wasted structure, then see the honest before-and-after size. Runs entirely in your browser — nothing is uploaded.
How to use the Compress PDF
- 01Drop your PDF in, or click to choose it.
- 02Click Compress and wait a moment while it is rebuilt.
- 03Check the size saved, then download the optimized PDF.
Frequently asked questions
How much smaller will my PDF get?
It depends. This tool losslessly rewrites the PDF using object streams, which removes structural bloat but keeps every pixel and character. Text-heavy or already-optimized PDFs may barely shrink, and we show you the real percentage rather than a made-up number.
Will it ruin the quality of images in my PDF?
No. The compression is lossless, so images and text are untouched. That also means it will not dramatically shrink an image-heavy scan the way lossy re-compression would — nothing is thrown away.
Is my PDF uploaded?
No — the file is rebuilt locally in your browser with pdf-lib, so your document never leaves your device.