PDF Compressor
Make PDFs smaller without uploading them anywhere. Downsample page images to a chosen DPI and JPEG quality for big savings on scans and image-heavy documents, or re-stream losslessly to rebuild the file with compact object streams and stripped metadata while keeping text and vectors intact.
How to use PDF Compressor
- Drop in your PDF (or click to browse).
- Choose "Downsample images" for maximum shrinkage, or "Lossless re-stream" to keep selectable text.
- Tune the DPI/quality (or the metadata option), click Compress, and download the smaller PDF.
Frequently asked questions
- How do I compress a PDF?
- Drop in the PDF, choose Downsample images for the biggest reduction or Lossless re-stream to keep selectable text, tune the settings, then click Compress and download the smaller file.
- Is my PDF uploaded to a server?
- No — compression runs entirely in your browser with pdf.js and pdf-lib, so the document never leaves your device.
- Why did "Downsample images" shrink my PDF so much?
- It re-renders every page as a JPEG at the DPI and quality you pick, which dramatically reduces size for scanned or image-heavy PDFs. The trade-off is that text becomes part of the image and is no longer selectable.
- When should I use "Lossless re-stream" instead?
- Use it for text or vector PDFs you want to keep editable/searchable. It rebuilds the file with compact object streams and removes metadata, giving modest savings without quality loss.
- What if the file gets bigger or barely changes?
- Some PDFs are already optimized. The tool shows the before/after sizes and percentage so you can compare — try the other method or a lower DPI/quality if needed.