🗜️ PDF Compress
Reduce your PDF file size for journal submission, email or storage. Files never leave your device.
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Size Stats
See before and after file sizes and exact percentage reduction.
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Reducing PDF file size for journal and email submission
Many journals impose file size limits on manuscript and supplementary file uploads — commonly 10–25 MB for the main manuscript and 50 MB for supplementary materials. Email attachments are typically limited to 10–25 MB. This tool reduces PDF file size in your browser without uploading files to any server.
What affects PDF file size
High-resolution embedded images are the primary driver of large PDF files. Text-only PDFs are typically small regardless of page count. A manuscript with high-resolution figures can easily exceed 100 MB. Reducing image resolution to 150–200 dpi (sufficient for digital review, and separate from your high-resolution submission files) typically reduces size by 60–80%.
When not to compress
Do not submit compressed figures as your final production files if the journal requires high-resolution images. Use compression only for the initial manuscript submission where a review-quality PDF is acceptable, and keep your original high-resolution files for the production stage after acceptance.