Compress PDF

Optimize PDF structure in your browser without downsampling images or rasterizing pages.

Add a PDF to get started

Drag and drop files here, or choose from your device.

Choose PDFChoose a file to add it to this workspace.

A practical guide

How to use Compress PDF

Choose a PDF. Password-protected PDFs are not supported.
PDF64 optimizes the PDF structure directly in your browser.
Download the optimized file if it is smaller than the original.

How compression works

PDF64 optimizes the internal structure of the PDF without intentionally reducing image quality or rasterizing pages. It does not downsample images, so this tool is best suited to PDFs where structural optimization can reduce file size.

How much smaller will my PDF be?

The result depends on the document. Some PDFs become smaller, while image-heavy or already optimized files may change very little. If optimization does not produce a smaller file, PDF64 keeps the original instead.

Processing and limits

Compression runs in your browser, so the PDF is not uploaded. Files can be up to 100 MB. Very large documents may still be limited by the memory and processing power available on your device.

Frequently asked questions

Does PDF64 reduce image quality?

This optimizer does not downsample or re-encode images. It focuses on optimizing PDF structure.

Why didn't my PDF become much smaller?

The file may already be optimized, or most of its size may come from images that this tool does not downsample.

Is my PDF uploaded?

No. Compression runs locally in your browser.