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Compress PDF Online – Reduce File Size

Compress large PDF files for email, WhatsApp, job applications, and government portals.

Select PDF File

or drag and drop here

SSL Secured Auto Delete Fast

Optimize PDF File Size Instantly with Precision Control

Don't settle for generic compression. ClonyPDF gives you intelligent modes tailored to your exact needs—from quick email attachments to strict government portal limits.

⚡ Smart Mode

Our AI analyzes your document to find the perfect balance between minimal file size and maximum readability.

  • Auto-detects image vs. text ratios
  • Maintains crystal-clear fonts
  • Best for general office and student use

🎯 Purpose Mode

Stop guessing sizes. Choose where you are uploading, and we automatically apply the correct optimization rules.

  • Gov Portals: Strict sub-500KB limits
  • Email/WhatsApp: Fast-share optimization
  • Job Boards: ATS-friendly resume formatting

⚙️ Advanced Mode

Need exactly 100KB? Take complete control over the compression engine with precise manual adjustments.

  • Input exact target file size (KB/MB)
  • Manual DPI and image quality sliders
  • Grayscale conversion options

How to Reduce PDF Size in 4 Simple Steps

No software installation required. Compress your documents securely directly from your browser.

Upload File

Drag and drop your PDF or tap to select from your device. We support files up to 100MB.

Select Mode

Choose Smart Mode for quick results, Purpose Mode for specific platforms, or Advanced Mode for manual control.

Compress

Click compress. Our cloud servers process your file in seconds, dramatically reducing the file weight.

Download Securely

Save your optimized PDF. Your original and compressed files are automatically permanently deleted after 1 hour.

Engineered for Real-World Workflows

We built ClonyPDF because standard PDF tools are frustrating, bloated, and compromise your privacy.

Typical PDF Sites

  • ✗ Blind "High/Medium/Low" compression
  • ✗ Adds annoying watermarks to free files
  • ✗ Forces you to create an account
  • ✗ Keeps your files on their servers indefinitely
  • ✗ Ruins scanned document clarity

The ClonyPDF Standard

  • ✓ Use-case optimization (Target size targeting)
  • ✓ 100% Watermark-free always
  • ✓ No signup required to process files
  • ✓ Auto-delete after 1 hour (256-bit SSL secured)
  • ✓ Text-preservation tech for scanned PDFs

Frequently Asked Questions

Everything you need to know about PDF compression and file security.

How to compress PDF without losing quality?
Use ClonyPDF's Smart Mode. It selectively compresses background data and redundant image metadata while preserving vector graphics and text clarity, ensuring your document looks identical to the naked eye.
How to reduce PDF size for email?
Most email providers restrict attachments to 20MB or 25MB. Select Purpose Mode > Email in our tool. It automatically optimizes DPI and images to guarantee your file easily slips under email attachment limits.
What is the best PDF size for government upload?
Government portals typically require PDFs to be under 500KB or 1MB. Using our Purpose Mode > Government Portal setting will dynamically compress your file to meet these strict legacy system requirements.
Can I compress a scanned PDF?
Yes. Scanned PDFs are essentially large images wrapped in a PDF file. ClonyPDF applies advanced image downsampling to reduce the file size significantly while keeping the scanned text legible.
Is it safe to compress PDFs online?
Absolutely. ClonyPDF uses 256-bit SSL encryption for all transfers. We do not look at, mine, or share your data. All uploaded and processed files are permanently and automatically deleted from our servers within 1 hour.
Can I compress a PDF to exactly 100KB?
Yes. Select Advanced Mode, enter "100" in the target KB field, and our engine will iteratively compress the document to hit that exact size threshold without destroying readability.
Does compression reduce image clarity?
Heavy compression will eventually reduce image DPI. However, ClonyPDF prioritizes lossless compression first. If aggressive compression is needed to hit a target size, we use intelligent downsampling to minimize pixelation.
How to compress a resume PDF without breaking ATS?
Applicant Tracking Systems (ATS) need selectable text. Standard compressors flatten resumes into images, breaking ATS. ClonyPDF's Purpose Mode > Job Application strictly compresses images and metadata while keeping text layers perfectly intact.
Why do PDF uploads fail on portals?
Uploads usually fail due to strict file size limits (e.g., max 2MB) or unsupported PDF versions. ClonyPDF not only reduces the size but saves the file in a standardized, highly compatible PDF format.
Is there any file limit for using ClonyPDF?
You can upload and compress PDF documents up to 100MB in size. If your file is larger, we recommend splitting the PDF first, which you can also do using our suite of document tools.

PDF Optimization Guides & Tips

Learn more about formatting documents for specific platforms and workflows.

Compress PDF for Email

Fit attachments within Gmail (25MB) & Outlook limits effortlessly.

Read Guide →

Compress PDF for WhatsApp

Share files instantly on mobile without "File Too Large" errors.

Read Guide →

Compress Large Scanned PDFs

Reduce heavy image-based scans while keeping text sharp.

Read Guide →

Compress for Loan Applications

Ensure bank statements & IDs upload smoothly to banking portals.

Read Guide →

Enhance Your Workflow

Explore our complete suite of PDF and Image tools. Fast, secure, and free.

🧩

Merge PDF

Combine multiple files
🗜️

Compress PDF

Reduce file size
🆔

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SSC/UPSC Photo Size
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JPG to PDF

Convert Images to PDF
✨

PNG to PDF

Fix Transparency
📤

PDF to PNG

Extract High Quality
🌐

PDF to WebP

Web Optimized Images
✂️

Split PDF

Extract specific pages
🔓

Unlock PDF

Remove passwords
🔒

Protect PDF

Encrypt with password
🔄

Rotate PDF

Fix page orientation
🗑️

Remove Pages

Delete unwanted pages