Compress PDF – Free, Fast & Private
Shrink PDF files locally in your browser — contracts, scans and reports never leave your device
How to compress a PDF
Choose or drag in your PDF — it stays on your device, nothing is uploaded.
Compression starts instantly and produces three versions: Smallest, Balanced and High quality.
Compare the sizes and download the version that fits.
About PDF compression
Most of a PDF's size is its embedded images: scans, photos and slide graphics. This tool re-compresses those images at a resolution appropriate for reading, directly in your browser — the text stays sharp, selectable and searchable.
Unlike other online PDF compressors, nothing is uploaded. That matters for PDFs more than anything else you compress: contracts, invoices, ID scans and medical documents stay on your device, always.
Frequently asked questions
It finds the images embedded in your PDF (scans, photos, graphics) and re-encodes them at a reading-appropriate resolution and quality, then rewrites the file with compact object streams. Text and vector content is never rasterized — it stays sharp at any zoom.
No. Compression runs entirely in your browser using WebAssembly-grade local processing. Contracts, invoices and ID scans never leave your device — there is no upload, no queue and no server that could retain a copy.
Yes. Only embedded images are re-compressed; the text layer, fonts, bookmarks, links and form fields are preserved as-is.
Scanned documents and photo-heavy PDFs typically shrink by 60–90%. Slide exports usually lose 40–70%. Text-only PDFs are already compact, so gains there are small — the result card always shows you the honest before/after numbers.
If a PDF is mostly text and vector graphics it is already well optimized, and there is little left to compress without damaging it. We only replace images when doing so genuinely saves space — we never inflate quality loss just to show a bigger percentage.
Rewriting a PDF always invalidates existing digital signatures — this is true of every PDF compressor. If your file contains a signature we tell you in the result, so you can decide whether the smaller copy or the signed original is the one to share.
Not directly — remove the password first (open it with the password and save an unprotected copy), then compress.
No. This tool targets screen reading and sharing. Print-production PDFs (CMYK images, spot colors, high-DPI requirements) are deliberately left untouched by our safety rules, so you may see little reduction — keep using your press workflow for those.
Yes — free and unlimited, with no watermark, signup or daily quota. Because processing happens on your device, we have no per-file server costs to charge for.
Up to 500MB per PDF, with no limit on the number of files. Very large scanned files are processed page by page to stay within browser memory.