Compress PDF
Re-save a PDF with compact object streams to reduce structural overhead when possible.
Why use this tool
01Select one PDF, re-save it locally with compact object streams, and download the result without uploading the file to a server.
This PDF workflow is designed for common document cleanup and handoff tasks where uploading files would add privacy risk or delay.
Processing runs in the current browser tab, so the practical limit is your device memory and browser support rather than a server quota.
How to use
02Quick checks before you copy
03Confirm the input is the format you intended.
Scan the result before using it in a document, URL, config, or message.
Copy only the output you need.
Use Cases
Run a browser-local compact re-save on a PDF with unoptimized internal data before deciding whether heavier compression is needed.
See whether a local object-stream re-save is enough before sending a document to an external compression service.
Some PDFs accumulate internal update data after edits. A compact re-save can reduce structural overhead without changing pages.
Compare the original and downloaded file sizes, then open the output locally to confirm appearance before sharing.
If a scan or image-heavy PDF stays large, use a dedicated image-compression workflow after confirming this first pass is not enough.
Tips & Tricks
- 01Best for structurally unoptimized PDFs
This tool re-saves the document with compact object streams. PDFs that were created by older software or incremental saves may shrink more than already optimized files.
- 02Scanned PDFs may need image downsampling
Large scanned PDFs are often dominated by embedded images. This browser tool does not expose image-quality controls, so those files may need a dedicated image-compression workflow for large reductions.
- 03Already optimized files may stay similar
If the downloaded file is close to the original size, the PDF was likely already using compact internal storage.
- 04Check quality before sharing
After compressing, open the downloaded file and zoom in on any images, charts, forms, or signatures before sending it to clients or submitting officially.
FAQ
04Is my PDF uploaded to a server during compression?
No. Compression runs entirely in your browser. Your file never leaves your device.
How much can I reduce a PDF's file size?
It depends on the file structure. PDFs with older or incremental internal storage may shrink noticeably, while already optimized PDFs or image-heavy scans may change very little because this tool does not downsample images.
Will compression reduce visual quality?
This tool does not expose quality settings or intentionally recompress images. It rewrites the PDF with compact object streams, so savings depend on the file structure. Always open the downloaded file and confirm text, images, and signatures still look right.
Can I compress a PDF multiple times?
You can, but repeated saves usually provide little benefit after the first compact-object-stream rewrite. If the first pass does not shrink the file enough, use a workflow that explicitly resizes or recompresses embedded images.
Will the compressed PDF open in all PDF readers?
Yes. The compressed output is a standard PDF compatible with Adobe Acrobat, Preview, Chrome, and all common PDF readers.
Does compressing a PDF remove any content?
No pages, text, or images are intentionally removed. This workflow reduces file size only when the PDF can be represented more compactly during the browser-side re-save.
What's the smallest file size I can achieve?
The minimum achievable size depends on the content. The tool cannot compress a PDF smaller than the raw information it contains.
Can I compress a PDF with owner restrictions?
If the file opens but has owner restrictions, use PDF Password to remove print, copy, or edit restriction flags before compressing. PDF Password does not remove an open password required to view encrypted PDFs.
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