PDF Compressor
Reduce PDF file size with object-stream optimization. Runs locally - deep image recompression coming soon.
Shrink a PDF's file size for email attachments or web uploads by optimizing its internal object streams and removing redundant structure, without changing the visible page content. Runs entirely in your browser with pdf-lib, so the file never leaves your device. Compression gains are most noticeable on PDFs with a lot of internal duplication or unoptimized structure; deep image recompression for image-heavy PDFs is planned as a future improvement.
Loading tool
How it works
- 01
Upload your PDF.
- 02
Click Compress.
- 03
Download the smaller PDF.
Details
- Category
- Documents & PDF
- Formats
- Runs
- In your browser
- Files uploaded
- No
- Cost per run
- Free
- Sign-in
- Not required
- Works offline
- Yes, once loaded
Last updated 2026-08-03
Common questions
How much smaller will my file get?
It varies by document - PDFs with unoptimized internal structure see the biggest gains, while already-optimized files shrink less.
Does compression reduce image quality?
Current compression targets object-stream and structural overhead, not image recompression, so visible image quality is unaffected.
Does it upload my PDF?
No - compression runs entirely in your browser using pdf-lib.
Will it always shrink the file?
Most PDFs shrink somewhat, but a file that's already tightly optimized may see minimal change.