PDF Compressor
PDF Compressor — reduce PDF file size by up to 90% without losing quality. Free online tool, no signup, no watermark. Compress any PDF instantly.
About PDF Compressor
The PDF Compressor reduces the file size of any PDF by up to 90% — making documents small enough to email, upload, share, and store without losing readable quality. Upload your PDF, click compress, and download a smaller file in seconds. No software to install, no account to create.
Large PDF files create friction at every stage of sharing. Email providers cap attachments at 10MB to 25MB, turning a 35MB brochure into an unsendable file. File upload forms on government sites, HR portals, and client portals often have strict limits that a scanned document easily exceeds. Sharing a PDF via messaging apps or cloud links is faster when the file is a fraction of its original size. All of these problems are solved by compression before sharing.
The compression engine works primarily by optimizing the images embedded in a PDF. Most large PDFs contain photographs, illustrations, or scanned page images stored at resolutions far higher than necessary for screen viewing or standard printing. A scanned document captured at 600 DPI contains roughly four times as much data as one scanned at 300 DPI — and the visual difference is negligible on screen or in a typical office printout. By resampling and re-encoding these embedded images at appropriate quality levels, the compressor achieves dramatic file size reductions while preserving readable clarity.
Text content in PDFs is already stored in a highly efficient format and typically contributes very little to file size. Compression makes the most dramatic difference on image-heavy documents: brochures, scanned contracts, photo portfolios, and multi-page reports with embedded charts or photographs. A text-only PDF of a few dozen pages may only compress by 10-20%, while the same-length document with embedded product photography might compress by 70-85%.
PDF metadata — bookmarks, hyperlinks, embedded fonts, table of contents entries, and document properties — is preserved through the compression process. The structure and navigability of your document remain intact.
Your file is processed to generate the compressed output and is not retained on the server. Free with no signup required.
Frequently asked questions
Most PDFs can be compressed by 50-90% depending on content. Image-heavy PDFs see the biggest reductions, while text-only files are already compact and compress less.
Our smart compression preserves text clarity and readability. Image quality may be slightly reduced at higher compression levels, but the result remains professional and print-ready.
No strict limit — you can compress large PDFs including multi-page reports and scanned documents. Processing time may vary for very large files.
Email providers typically limit attachments to 10-25MB. Many web upload forms have similar constraints. Cloud storage and document management systems benefit from smaller files for faster syncing and lower storage costs. Compressed PDFs also load faster when shared as links.