How much will my PDF be compressed?

Lossless compression typically reduces size by 10–30%. Medium (default) achieves 40–70%. High compression can reach 60–90% reduction.

Will compression reduce visual quality?

Lossless mode maintains full quality. Medium and High modes re-encode images — use the side-by-side preview to check quality before downloading.

What is the Custom mode?

Custom lets you set the exact JPEG quality (1–100), DPI target, grayscale conversion, and font stripping for precise control.

Does this work for scanned PDFs?

Yes — scanned PDFs (which are essentially images) benefit significantly from image re-encoding compression.

📄 PDF Tool Free · No Upload · No Account

Compress PDF Files Online for Free

Compress PDF files using lossless or lossy algorithms. Choose from preset levels or customize DPI, JPEG quality, and more for the perfect balance of size and quality.

Files never uploaded No account required Unlimited use, free forever WebAssembly-powered

Drop your file here, or click to browse

Single PDF file

Or press Ctrl+V to paste

How to Compress PDF

Upload your PDF

Drop your PDF into the upload area or click to browse.
Choose compression level

Select Low (lossless), Medium, High, or Custom. Adjust settings and preview the quality comparison.
Compress and download

Click "Compress & Download" — see the before/after size savings and download your optimised PDF.

Features

4 compression levels including custom
Side-by-side quality preview
Before/after file size comparison
Custom DPI and JPEG quality controls
Grayscale conversion option

Frequently Asked Questions

How much will my PDF be compressed?: Lossless compression typically reduces size by 10–30%. Medium (default) achieves 40–70%. High compression can reach 60–90% reduction.
Will compression reduce visual quality?: Lossless mode maintains full quality. Medium and High modes re-encode images — use the side-by-side preview to check quality before downloading.
What is the Custom mode?: Custom lets you set the exact JPEG quality (1–100), DPI target, grayscale conversion, and font stripping for precise control.
Does this work for scanned PDFs?: Yes — scanned PDFs (which are essentially images) benefit significantly from image re-encoding compression.