Compress PDF
Select PDF to Compress
Reduce your file size while maintaining the best possible visual fidelity.
Select or Drop a PDF file
Drag and drop your document here, or browse files from your computer
Basic PDF optimisation
This tool repacks PDF objects. It does not downsample images or offer different compression levels. Already optimised files may stay the same size; in that case the original bytes are returned. Keep the original and check the output.
Compress PDF Online — Reduce PDF File Size Without Losing Quality
Attempt basic PDF object optimisation and compare the saved size with the original.
For an email attachment, process a copy and compare the two sizes shown. If they match, the original bytes have been returned because repacking did not produce a smaller file.
A smaller file is not guaranteed. This tool repacks PDF objects; it does not downsample images or provide different compression levels. Copying pages can affect document-level forms, bookmarks or digital signatures.
How to Use Compress PDF in 3 Easy Steps
Prepare the input, process it, and verify the saved output.
Prepare your input
Select a PDF and keep a separate copy of the original document.
Process the document
Run the optimisation and compare the reported sizes.
Check the saved result
Zoom into small text and images, check whether text remains selectable, and confirm the recipient file-size limit.
Why Use OneToolPDF for Compress PDF?
Engineered for productivity, privacy, and precision formatting.
Practical example
For an email attachment, process a copy and compare the two sizes shown. If they match, the original bytes have been returned because repacking did not produce a smaller file.
Limitations to know before processing
A smaller file is not guaranteed. This tool repacks PDF objects; it does not downsample images or provide different compression levels. Copying pages can affect document-level forms, bookmarks or digital signatures.
Browser processing and file handling
This available tool processes document content in your browser. Choosing a file does not send its contents to our conversion server.
Frequently Asked Questions
Common questions regarding Compress PDF.
Related PDF Tools
Combine workflows with other high-performance tools on OneToolPDF.
Merge PDF
Combine the pages of two or more PDFs in the file order you choose.
Repair PDF
Attempt basic PDF recovery by checking boundary markers and re-saving a file that the parser can read.
Edit PDF
Add text, drawings and shapes over existing PDF pages using the editing controls.
Rotate PDF
Change the viewing orientation of selected PDF pages in quarter turns.