Compress PDF
Upload a PDF and download a smaller version, with the before/after size shown.
Overview
This tool re-serializes a PDF's internal object structure — deduplicating repeated objects and packing them into compressed object streams — which meaningfully shrinks PDFs that carry a lot of redundant structure, such as forms or files re-saved by older tools.
It's honest about a real limitation: this is structural compression, not image recompression. A PDF whose size is dominated by large, already-compressed embedded photos won't shrink much here — there's currently no image-recompression step in this pipeline.
Examples
Compressing a form-heavy PDF
form.pdf (4.2 MB)
compressed.pdf (~2.8 MB)
How It Works
- Choose a PDF file from your device.
- Click Compress. The file is uploaded, its internal structure is deduplicated and repacked, and the result is returned.
- Check the before/after file size shown, then click Download to save the compressed PDF.
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
- If your PDF is mostly large images, this tool likely won't shrink it much — the savings come from structural redundancy, not image quality reduction.
- Try this on a form-heavy or repeatedly-edited PDF first to see the biggest gains.
FAQ
Yes. Compression requires a real PDF library, so the file is uploaded, processed in memory, and the result returned — nothing is stored.
No. This tool only deduplicates and repacks the PDF's internal object structure — it doesn't recompress embedded images, so visual quality is unchanged.
If a PDF's size is mostly large embedded images, or it was already saved efficiently, there may be little redundant structure left to remove.