Compress PDF
About PDF Compression
This tool helps you reduce the file size of your PDF documents:
- Light: Lightest touch — core structural optimisation (lossless)
- Default: Balanced structural optimisation (lossless)
- Extreme: Maximum structural optimisation (lossless)
Note: Compression is lossless — your text and images are not re-encoded, so quality is preserved. The tool reports the before/after size and never returns a file larger than the original.
Tips for Best Results
- All levels are lossless — they optimise the file's structure without re-encoding images
- Default is a good balance; Light is the lightest touch and Extreme applies the most passes
- Image-heavy PDFs may shrink only a little (their images are already compressed)
- The result shows the exact before/after size — and never returns a larger file
- Always check the compressed file before sharing to verify quality
Frequently Asked Questions
Upload your PDF, select a compression level, and click Compress PDF — the tool reduces your file size directly on our secure servers with no software to install.
No — compression is lossless. It optimises the file's internal structure (object and content streams, unused data) without re-encoding your text or images, so quality is preserved exactly. Files that are already image-heavy may shrink only slightly.
It depends on the content. PDFs with redundant structure or uncompressed streams shrink the most; already-optimised or image-heavy files may shrink little. The tool shows the exact before/after size, and if a file can't be made smaller it keeps your original rather than handing back a larger one.
Processed on ISO 27001-certified UK servers.
Files are encrypted in transit and automatically deleted.
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