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Compress a PDF online

Compress a PDF online to reduce its file size, with nothing to install. Free and private. Tool is being set up.

100% private: this tool runs entirely in your browser. Your file never leaves your device — nothing is uploaded, nothing is stored.

Drop files, paste, or click to browse

Files are processed in your browser — they never leave your device.

Add a file to continue.

Compress a PDF online

Compressing a PDF online means there is nothing to install and no desktop app to license — you open this page in any browser, add your file, and get a smaller version back. Reducing file size makes a PDF faster to email, quicker to upload to a form, and lighter to store, which is why an online compressor is handy when you are away from your own computer or on a managed machine where you cannot install software. The amount of reduction depends on the file: PDFs built from images and scans shrink the most because their embedded pictures can be downsampled, while text-only documents are already compact and change less. For high-resolution work that must stay print-perfect, keep the compression light. Files sent for online compression are handled under our strict privacy promise — encrypted in transit, never logged, and automatically deleted within about an hour, so nothing of yours is retained.

Frequently asked questions

Do I need to install anything to compress online?
No. It runs in the browser, so there is nothing to download — useful on work or shared computers.
How much smaller will my PDF get?
It depends on the content. Image- and scan-heavy PDFs shrink the most; text-only files are already small and change less.

More ways to use Compress PDF