Compress PDF
Upload a PDF, choose recommended or lossless compression, and download a smaller version with the before and after size shown.
Overview
Most of a typical PDF's size is its images: scanned pages, photos, and screenshots. The recommended setting re-encodes those images as JPEG wherever that makes them smaller, and also rewrites the file's internal structure with maximum-level compression. For image-heavy documents that's usually where the big savings are.
Lossless mode leaves every image exactly as it is and only recompresses the PDF's internal structure. Use it when exact image fidelity matters, such as for print-ready artwork or legal scans. Savings are much smaller, and a PDF that was already saved efficiently may not shrink at all.
You never get a bigger file back. If compression can't make a PDF smaller, the original is returned unchanged and the tool tells you so.
Examples & Sample Data
Image-heavy PDF, recommended setting
report.pdf (4.6 MB, three pages with a large embedded photo each)
compressed-report.pdf (1.1 MB, 76% smaller)
How It Works
- Choose a PDF file from your device, or drop it onto the tool.
- Pick Recommended to recompress images, or Lossless to leave images untouched.
- Click Compress. The file is processed on the server and deleted as soon as the result is sent back.
- Check the before and after size, then click Download to save the compressed PDF.
Common Use Cases
Fitting an email attachment size limit
Shrink a PDF before emailing it or uploading it somewhere with a strict file size cap.
Cleaning up a PDF re-saved by an older tool
Files that have been edited and re-saved repeatedly often accumulate redundant objects that this tool removes.
Tips & Best Practices
- Start with Recommended. Switch to Lossless only if you notice a problem with image quality in the result.
- Text-only PDFs are already compact, so expect small savings. The biggest reductions come from scans and documents full of photos.
- If a PDF is password-protected, remove the password with Unlock PDF first.
Frequently Asked Questions
Yes. Compression runs with qpdf on the server, so the file is uploaded, written to a private temporary folder while it's processed, and deleted as soon as the result is sent back. Nothing is kept.
With the Recommended setting, images may be re-encoded as JPEG, but only where that makes them smaller. Photos usually look the same, while sharp-edged graphics can show slight artifacts. Choose Lossless to keep every image exactly as it was.
The PDF was probably already well optimized, for example a text-only document or one whose images are already compressed JPEGs. When compression can't reduce the size, the original file is returned unchanged.
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