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How it works
- 1
Upload your PDF
Drag and drop or browse to select the PDF file you want to compress.
- 2
Automatic lossless compression
The tool applies lossless compression — deflating uncompressed streams and removing redundant objects — while preserving full document quality.
- 3
Review results and download
See the original and compressed file sizes side by side with the percentage saved. If the file is already well-optimized, you'll see a notice explaining that further compression isn't possible.
Features
- Lossless compression
- Text, images, and vector graphics remain at their original quality. The tool compresses internal PDF streams without re-encoding or downsampling content.
- Before and after comparison
- After compression, a summary shows the original size, compressed size, and exact percentage saved — so you know exactly how much space you gained.
- Already-optimized detection
- If compression would increase the file size (because the PDF is already well-optimized), the tool warns you instead of producing a larger file.
Frequently asked questions
- Does compression reduce the quality of my PDF?
- No. The tool uses lossless compression techniques such as stream deflation. Text, images, and vector graphics remain at their original quality.
- How much can the file size be reduced?
- Results depend on the document. PDFs with uncompressed streams or redundant objects typically see significant reductions. Already-optimized files may see smaller gains, and the tool will warn you if compression would increase the file size.
- Is my file uploaded to a server?
- No. Compression runs entirely in your browser using WebAssembly. Your files never leave your device.
- Can I compress multiple PDFs at once?
- Currently the tool compresses one file at a time. You can process additional files immediately after each download.