How to Use PDF Compressor
- Step 1: Select or drop your PDF document into the compression workspace.
- Step 2: Choose a compression preset: Low (high visual quality), Recommended (balanced), High, or Extreme.
- Step 3: View original and compressed file sizes in the live comparison panel.
- Step 4: Click Compress & Download to save your optimized PDF document.
Settings & Controls Explained
One Resizer's PDF Compressor provides specialized browser-local controls tailored to its workflow:
- Compression Presets: Choose between Low (90% quality retention), Recommended (balanced size and fidelity), High, and Extreme compression.
- Image Stream Re-rasterization: Re-encodes embedded high-resolution photo streams at optimized DPI thresholds.
- Live Savings Calculator: Real-time display of original bytes, compressed bytes, and percentage reduction.
Supported Formats & Technical Capabilities
| Specification | Technical Capability |
|---|---|
| Accepted Input Formats | PDF (.pdf) |
| Output File Formats | PDF (.pdf) |
| Processing Engine | Client-Side PDF.js & PDF-Lib Engine |
| Network Privacy | Local browser processing (0 bytes uploaded) |
Best Practices & Key Recommendations
- Use Recommended compression for standard business reports, application forms, and ebooks.
- Use Extreme compression when meeting strict portal upload limits (e.g. under 1 MB or 2 MB ceilings).
- Digital PDFs containing mostly vector text compress faster than heavy scanned image documents.
Troubleshooting & Common Issues
- Compressed PDF file size did not decrease significantly: If the source PDF contains mostly digital vector text and fonts without large bitmap images, compression savings will be minimal because text is already highly compact.
- Password-protected PDF fails to load: Unlock the document using PDF Unlock before running compression.