Compress PDF
Reduce PDF file size — including to targets like 100KB or 200KB — with browser-side compression that keeps your files private.
About the Compress PDF
This free PDF compressor reduces file size directly in your browser — your document is never uploaded to any server. That makes it safe for compressing sensitive files like signed contracts, ID scans, bank statements and application documents. Choose lossless mode to shrink the file while keeping text selectable, or strong mode for maximum size reduction when a portal enforces a strict upload limit.
Many government portals, job application systems and exam registration sites cap uploads at 100KB, 200KB or 500KB. The strong compression mode converts each page to an optimized JPEG image at your chosen quality, often shrinking scanned PDFs by 70–90%. Use the built-in 100KB and 200KB presets as a starting point, then fine-tune the quality slider until the file fits.
Lossless mode rebuilds the PDF with compressed object streams — a safe default that keeps text, links and vector graphics fully intact, typically saving 5–30% on unoptimized files. The tool always shows the before and after sizes plus the percentage saved, so you can compare modes and download only when you're happy with the result.
How to Use the Compress PDF
- 1Add the PDF you want to shrink — the original size is shown immediately.
- 2Pick a mode: Lossless (keeps text selectable) or Strong (converts pages to images for maximum savings).
- 3In Strong mode, adjust the quality slider or click the ~100KB / ~200KB presets.
- 4Click "Compress PDF" and review the before/after sizes and percentage saved.
- 5Download the compressed PDF — repeat with different settings if you need it smaller.
Frequently Asked Questions
How do I compress a PDF to 100KB for free?
Add your PDF, switch to Strong mode and click the "Aim for ~100 KB" preset, which lowers image quality and resolution aggressively. Compress and check the resulting size — if it's still too large, drag the quality slider lower and compress again. Short documents of one to three pages usually reach 100KB easily; very long documents may only get close.
Will compressing my PDF make the text unreadable?
Lossless mode never touches your text — it stays sharp, selectable and searchable. Strong mode converts pages to JPEG images: at the default 70% quality text remains perfectly readable on screen and in print, but it can no longer be selected or searched. For forms you must submit as scans, this is normally acceptable.
Is it safe to compress confidential documents with this tool?
Yes. Compression runs entirely in your browser — the PDF is never transmitted over the internet, stored on a server or seen by anyone else. This makes it suitable for salary slips, tax documents, medical reports and identity documents that many people rightly hesitate to upload to typical online compressors.
Why did lossless compression barely reduce my file size?
Lossless mode restructures the PDF and compresses its internal object streams, which helps most on files saved by older or inefficient software. If your PDF was already optimized, or its size comes mostly from photos and scans, there is little redundant data to remove. Switch to Strong mode, which recompresses the actual page images and typically saves far more.
What's the difference between compressing to 100KB and 200KB?
Both presets use Strong mode but with different quality and resolution settings: the 100KB preset uses lower JPEG quality and resolution for maximum shrinkage, while the 200KB preset keeps pages noticeably crisper. Since the final size depends on your page count and content, treat presets as starting points and fine-tune with the slider.
Can I compress a password-protected PDF?
No — encrypted PDFs can't be read without their password, so the tool will ask you to unlock the file first. Open it in any PDF viewer with the password and save or print it to a new, unprotected PDF, then compress that copy. You can re-apply protection afterwards with other software if needed.