PDF Compressor
Upload a PDF to strip metadata, clear author and title information, and optimise the file structure. Works best on text-heavy documents and Word-exported PDFs. Free, no signup, runs in your browser.
Upload PDF or drag and drop
PDF files only
How to use this tool
- 1Click the upload area or drag your PDF file onto it.
- 2The original file name and size are shown once uploaded.
- 3Click 'Compress PDF'. The tool removes metadata and optimises the internal file structure.
- 4Review the output file size and savings percentage, then click 'Download compressed PDF'.
Example
A 15-page report exported from Microsoft Word as a 4.2 MB PDF compresses to approximately 2.8 MB by removing embedded metadata, author information, and redundant internal objects - a 33% reduction.
A contract PDF contains author name, company, and creation date in its metadata. After compressing, the metadata is stripped. The layout, text, and images are unchanged but the file contains no identifying information.
Common use cases
- Reducing a Word-exported PDF to fit a 10 MB email attachment limit
- Stripping author, software, and creation metadata before sharing a PDF externally
- Cleaning up a PDF generated by a word processor that embeds unnecessary metadata and redundant objects
- Making a report or contract document smaller before uploading to a portal with a file size limit
Common mistakes
- Expecting large reductions from scanned PDFs - scanned PDFs consist mainly of compressed images. This tool optimises structure and removes metadata, but cannot re-compress the embedded images. For scanned PDFs, a server-side tool like Adobe Acrobat or Smallpdf is needed.
- Running compression multiple times expecting cumulative savings - after the first compression, further runs give diminishing returns. Once metadata is removed, there is little left to strip.
- Using this instead of reducing the source document - if the PDF is large because of high-resolution images embedded from Word or InDesign, compress the images in the source application before exporting to PDF.
- Not verifying the output displays correctly - always open the compressed PDF and check it renders properly before sending.
Frequently asked questions
How much will my PDF shrink?
Results depend heavily on the file type. Text-heavy PDFs exported from Word or Google Docs often shrink by 20-50%. Scanned PDFs or those dominated by images may shrink by less than 5% because the size is in the image data, not the metadata.
Does compression affect the text, layout, or images?
No. Text, images, fonts, and layout are preserved exactly. The tool only removes metadata (author, title, creation date, software) and optimises the internal file structure.
What metadata is removed?
The tool clears the PDF's title, author, subject, keywords, creator, and producer fields. These fields often contain software version numbers, author names, or company information that you may not want to share publicly.
Why is the reduction small for my PDF?
If the PDF contains high-resolution embedded images (common in scanned documents or design exports), most of the file size is in the image data. This tool cannot re-compress images. For those PDFs, Adobe Acrobat or Smallpdf with image downsampling will give better results.
Are my files uploaded to a server?
No. All processing happens in your browser using the pdf-lib library. Your PDF files never leave your device.
Can this open password-protected PDFs?
No. The tool cannot process password-protected or encrypted PDF files. Remove the password using a PDF application before uploading.
Will the compressed PDF work everywhere?
Yes. The output is a standard PDF that opens in any PDF viewer. The optimisation uses object streams that are compatible with PDF 1.5 and later, which covers virtually all current devices and software.
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