How to Compress a PDF Online (Free)
A scanned contract that's too big to email, an application portal with a 5MB upload cap, a PDF full of high-res photos — here's how to shrink a PDF's file size without installing anything.
Steps
- Upload your PDF at Stelluna's Compress PDF — up to 50MB.
- Pick a quality level. Low for the smallest file, medium for a balance, high if sharpness matters most.
- Click "Compress". Each page is re-rendered and re-encoded, right in your browser.
- Check the size comparison. See exactly how much smaller the new file is before downloading.
- Download. A new, smaller PDF with the same number of pages.
Ready to try it? Free, instant, your file never leaves your device.
Open Compress PDFWill I still be able to select or search the text?
No — compression works by rebuilding each page as an image, which is the only file-size-reduction method that needs zero server involved. That means text is no longer selectable or searchable after compressing. If you need to keep text selectable, skip compression and instead try Stelluna's Split PDF or Organize PDF to cut a large document down to just the pages you need.
FAQ
Is it free?
Yes — no account, no watermark, no limit on how many times you use it.
Does my PDF get uploaded anywhere?
No. Compression runs entirely in your browser — your file never leaves your device.
How much smaller will my file get?
Depends on the content — scanned or image-heavy PDFs shrink a lot, PDFs that were already mostly small text see less difference.
Which quality level should I pick?
Medium works for most cases. Use low only if you need the absolute smallest file (e.g. a strict upload limit), and high when the PDF has photos or fine print that need to stay sharp.
Can I compress a password-protected PDF?
Not currently — encrypted PDFs need their password removed first.