PDF Tools
Compress PDF
Reduce your PDF file size by stripping metadata and optimizing the internal structure — all in your browser.
Upload a PDF to compress
What browser-based compression can and can't do
This tool re-saves your PDF with optimized object streams and removes document metadata (author, title, keywords, etc.). For PDFs with redundant internal structure, savings can be significant. However, it cannot recompress embedded images or reduce image quality — for that, you would need a server-side tool that re-encodes images at lower resolution.
How to compress a PDF
- Click Add file and select your PDF, or drag it in.
- Click Compress — the tool re-saves the PDF with optimized structure and stripped metadata.
- Download the smaller PDF. The result size depends on how much redundant structure the original had.
Worked example
A 3.4 MB contract PDF needs to go through an email gateway that rejects anything over 2 MB. You compress it in the browser and download a 2.1 MB copy — under the limit — with the text intact. The savings come from removing the document metadata and rebuilding the internal structure; the visible content is unchanged. Because nothing was uploaded, the contract's terms stayed on your machine.
Frequently asked questions
- How does browser-based PDF compression work?
- The tool re-saves your PDF with optimized internal structure and strips metadata (author, title, keywords). This can reduce file size by removing unused objects and rebuilding the PDF more efficiently. It does not recompress embedded images.
- Why is the compression small for my PDF?
- If your PDF is already well-optimized or mostly consists of compressed images, there is little redundant data to remove. Browser-based compression primarily cleans up the PDF structure — it cannot reduce image quality or recompress JPEG streams.
- Is my PDF uploaded to a server?
- No. The entire process runs in your web browser using the pdf-lib library. Your file never leaves your device.