Why compress a PDF?
PDFs balloon in size fast — a handful of scanned pages or high-resolution images can turn a document into tens of megabytes, which is a problem for email attachment limits, slow uploads, or just storage space. Compressing shrinks the file, usually at the cost of some image sharpness.
How this tool works
This compressor renders each page of your PDF to an image at a reduced scale and quality, then rebuilds a new, smaller PDF from those pages — entirely inside your browser tab using open-source libraries (pdf.js to read the PDF, jsPDF to rebuild it). No file is uploaded anywhere.
Important trade-off: because each page becomes an image, any text in the original PDF is no longer selectable, searchable, or copyable in the compressed output. This approach works best for scanned documents, photo-heavy PDFs, or anything you mainly need to view rather than edit or search. If you need to preserve selectable text, keep your original PDF and only compress a copy.
Choosing a level
- Low — light compression, best for keeping text and images crisp.
- Medium — good balance for sharing and email attachments.
- High — maximum size reduction, more visible quality loss.