Choose your PDF
Select one PDF from your device or drop it into the compressor.
FREE PDF TOOL
Compress PDF Online
Reduce PDF file size online for free. Choose a compression level, compare the original and compressed sizes, and download the result — no account required.
Drop a PDF here
or choose a PDF from your device
One PDF at a time✓ Browser-based processing✓ No account required✓ Simple downloads
Your PDF
Reading PDF…
Original size—
Pages—
ProcessingOn your device
Compression level
Compression works best on PDFs containing photos or scanned pages. Text-only PDFs may already be highly optimized.
Ready to compressWe’ll optimize the PDF and show you the result before download.
✓
Your compressed PDF is ready
Compression complete.
Original—
Compressed—
Saved—
Your PDF is read and compressed directly in your browser. Octumi does not upload the selected PDF in this version.
QUICK GUIDE
How to compress a PDF
Make a PDF smaller for email, uploads or sharing in a few simple steps. Octumi shows the resulting file size before you download it.
Pick a compression level
Choose Light, Recommended or Strong depending on the balance you want.
Compress the PDF
Octumi processes each page in your browser and creates the compressed PDF.
Compare and download
See the original size, compressed size and percentage saved before downloading.
COMPRESSION LEVELS
Light, Recommended or Strong?
Light prioritizes image quality with a smaller reduction. Recommended aims for a useful balance of quality and file size. Strong targets a smaller file with more image-quality reduction.
GOOD TO KNOW
Why some PDFs shrink more than others
Compression works best on PDFs containing photos or scanned pages. Text-only or already optimized PDFs may not become meaningfully smaller, and Octumi will tell you when there is no useful reduction at the selected level.
FAQ
Compress PDF FAQ
Is Octumi's PDF compressor free?
Yes. You can use the Compress PDF tool without creating an Octumi account.
Which compression level should I use?
Recommended is a good starting point. Choose Light when image quality matters more, or Strong when reducing file size matters more.
Will PDF compression reduce image quality?
It can. Octumi rebuilds PDF pages using compressed image data, so stronger compression can reduce image quality. Keep your original PDF if you may need the highest-quality version later.
Why did my PDF not become smaller?
Some PDFs are already highly optimized. If Octumi cannot produce a useful reduction at the selected level, it tells you instead of presenting a larger file as a successful compression.
Does Octumi upload my PDF for compression?
No. In this version, the selected PDF is read and compressed directly in your browser. The PDF libraries used by the page are loaded from third-party CDNs.