Compress PDF
Shrink a PDF by re-rendering its pages as compressed images. Best for scanned or image-heavy PDFs. Runs in your browser.
Drop a PDF here, or click to choose.
Note: rasterizes pages — text becomes non-selectable
How to compress a PDF
- Set resolution and quality. Lower values shrink the file further at the cost of sharpness.
- Add your PDF. Drop the file onto the box to re-render its pages locally.
- Download. Save the compressed file once it's smaller than the original.
What happens to your file
Compression works by rendering each page to a compressed image and rebuilding the PDF from those images, entirely in the current browser tab. The original file is never uploaded to OpenToolkit.
Because pages are rasterized, this works best for scanned or image-heavy PDFs. Text-heavy PDFs are often already efficiently encoded and may not shrink — keep the original in that case.
What this compressor supports
Common reasons to compress a PDF
- Get a scanned document under an email attachment or upload-form size limit.
- Shrink a photo-heavy report before archiving or sharing it widely.
- Reduce storage use for a large batch of scanned records.
- Speed up loading a document-heavy page or app.
Frequently asked questions
Are my files uploaded anywhere?
No. Pages are re-rendered and reassembled locally in your browser tab; the file is never sent to OpenToolkit.
Why didn't my file get smaller?
Text-only PDFs are usually already compact, and rasterizing them can make them larger, not smaller. This tool helps most with scanned pages or PDFs full of large images.
Will my text still be selectable afterward?
No — pages become flattened images, so text is no longer selectable or searchable. Keep the original if you need selectable text.
What settings should I use?
Start around 150 DPI with medium quality for readable scans at a much smaller size, then raise DPI if fine print becomes hard to read.
Can I compress a password-protected PDF?
Not directly. Unlock it in a PDF application first and compress the unprotected copy.
I need to redact content, not just shrink the file — is that different?
Yes — use PDF Redaction for permanently covering sensitive content.
Related guides
Last reviewed: August 2026