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Compress PDF Online
Reduce PDF file size by optimizing and re-saving. Compare original vs compressed size.
About compress pdf
Reduce PDF file size by optimizing and re-saving. Compare original vs compressed size.
The PDF is opened and rewritten locally with pdf-lib and PDF.js compiled for the browser. Nothing is uploaded, nothing is stored, and the finished file downloads straight from your browser — which makes it a safe choice for contracts, invoices and anything confidential.
Features
- Compare original vs compressed size.
- Processed locally with pdf-lib — files never leave your device
- Safe for contracts, invoices and confidential documents
- No watermark and no page limit set by us
- Free, with no account required
- Works on desktop, tablet and phone
How to compress pdf online
Open your PDF
Drag and drop the PDF onto the tool or click to choose it from your device.
Choose your options
Compare the original and compressed size; re-run with different settings if needed.
Download the new PDF
Click Download to save the updated document. The file was processed locally and is not stored anywhere.
Frequently asked
Is my PDF uploaded to a server?
No. Compress PDF Online runs entirely in your browser using pdf-lib and PDF.js compiled for the browser. Your PDF never leaves your device and we don’t store anything.
Which formats are supported?
Standard PDF files of any version. Password-protected PDFs need to be unlocked first.
Is there a file size limit?
We don’t impose one. Very large PDFs (hundreds of MB) depend on your browser’s available memory.
Is Compress PDF free? Do I need an account?
Yes, it is completely free and there is no account, sign-up or watermark. It is one of 78 free browser tools from ModelsGroup.
Does it work on my phone?
Yes. It works in Safari and Chrome on iPhone, iPad and Android; open PDFs from Files or your downloads.
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