Compress PDF
Reduce PDF file size without losing quality — instantly, in your browser.
Optimize Your PDF File Size Instantly
Large PDFs create problems: email clients reject them, upload forms refuse them, and sharing becomes slow. Our Compress PDF tool resolves this by intelligently restructuring the internal data of your PDF to eliminate waste without visually degrading the content.
How Compression Works
PDF files accumulate redundant objects over time — deleted content, unused fonts, duplicate image streams. Our engine uses object stream compression via pdf-lib to strip inefficiencies and re-pack the document structure, which can reduce file size depending on the source document.
Common Use Cases
- PDFs generated by Microsoft Word or Google Docs (often over-optimised)
- Documents that have been edited multiple times
- Reports that need to fit common email attachment limits
- Files containing embedded thumbnails or preview caches
Privacy-First Compression
Many compression services process your files on their servers, creating a privacy risk for sensitive business or legal documents. PDFMarkr compresses entirely inside your browser — your file never travels anywhere.
Frequently Asked Questions
It varies by document. Some files change only slightly, while structurally bloated PDFs can shrink more noticeably.
No. Our compression targets structural redundancy, not image pixel data.
No. We process files of any size locally.
Currently one file at a time for compression. Use Merge first if you want to compress a combined document.
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