MetoolzyPDF 圧縮
High Compression
Reduce PDF document file size by up to 90% without losing text readability.
Flexible Presets
Pick Extreme, Recommended, or High Quality, or configure resolution and quality sliders.
100% Client-Side Privacy
All processing occurs locally in your browser. Files never touch any remote server.
Batch & ZIP Download
Compress multiple PDF files in one go and download individually or packaged into a single ZIP archive.
PDF 圧縮について
PDF Compress allows you to drastically reduce the file size of your PDF documents directly inside your web browser. Perfect for shrinking oversized resumes, scanned paper documents, financial statements, and presentation slides so they can be emailed, submitted through portal forms, or stored efficiently. Utilizing PDF.js rendering and WebAssembly PDF stream packing, the tool re-encodes embedded image streams and structures at optimal DPI and JPEG quality levels. Because all operations run client-side on your device, sensitive personal information, legal agreements, and corporate contracts remain strictly private and never traverse the internet.
PDF 圧縮の使い方
- Click the upload area or drag and drop one or more PDF files into the tool.
- Select a compression preset: "Recommended" for a balance of quality and size, "Extreme" for maximum compression, or "Custom" for manual tuning.
- Click "Compress PDF" (or "Compress All") to start the browser optimization process.
- Observe the page-by-page progress bar as the document is optimized.
- Review the before-and-after file size and savings percentage.
- Click "Download" to save your compressed PDF, or "Download All (ZIP)" if processing multiple files.
よくある質問
Are my PDF files uploaded to any server?
No. All compression is performed entirely client-side inside your web browser using WebAssembly. Your documents and sensitive information never leave your device.
Which compression level should I choose?
"Recommended" is ideal for 90% of documents, offering a significant size reduction while preserving crisp text. "Extreme" gives the smallest possible file size (great for strict email attachments or government portal limits under 2MB). "Less Compression" keeps high visual fidelity for printing.
Can I compress multiple PDF documents simultaneously?
Yes. You can drop several PDF files at once. The tool compresses them sequentially to prevent excessive browser memory consumption, and you can download them individually or bundled into a ZIP file.
Why did my PDF size not change significantly?
If a PDF contains only vector text with no embedded photographs or scanned images, or was already heavily compressed by other tools, further compression might yield smaller gains. The tool will clearly show you if a file is already optimized.
Are password-protected PDFs supported?
PDFs with owner permissions/restrictions are supported via ignoreEncryption. However, PDFs protected by an open password cannot be decrypted in the browser without entering the password first.
The Complete Guide to PDF Compress: Fast, Secure & Free Online Compressor
Professional, secure, client-side PDF Compressor designed to shrink PDF file sizes by up to 90% without compromising legibility.
In digital communication, file size limits are everywhere. Email attachments usually cap out at 10–25MB, while job boards, legal portals, university admission systems, and tax filing websites often enforce strict 1MB or 2MB ceilings. PDF Compress on Metoolzy solves this challenge instantly: reduce oversized documents to lightweight, web-ready PDFs directly in your browser with zero data uploads.
Why Choose Metoolzy's PDF Compressor?
- 100% Client-Side Privacy: Your sensitive contracts, financial statements, and resumes never leave your computer or phone. Everything runs locally in your browser via WebAssembly and PDF.js.
- Intuitive Compression Presets: Choose from Extreme (maximum compression for strict upload limits), Recommended (optimal balance for 90% of documents), or High Quality (crisp text and images for printing).
- Custom Precision Controls: Fine-tune resolution (DPI) and JPEG quality sliders to match your exact size target.
- Batch Processing & ZIP Download: Compress multiple PDF documents in one batch and download them individually or combined into a single ZIP archive.
- Completely Free with Zero Limits: No account registration, no file size caps, and no watermarks added to your documents.
How to Compress PDF Files in 3 Simple Steps
- Upload Files: Drag and drop one or more PDF files into the drop zone, or click to browse files from your device.
- Select Preset: Pick your preferred compression level (Recommended, Extreme, High Quality, or Custom).
- Compress & Download: Click Compress PDF (or Compress All), watch the real-time progress, and click Download to save your optimized document.
Feature Comparison Table
| Feature | Metoolzy PDF Compress | Cloud-Based Compressors | Desktop Applications |
|---|---|---|---|
| Data Privacy | 100% Local (Never leaves device) | Uploaded to remote third-party cloud | Local (Requires installation) |
| File Size Limit | Unlimited (Browser memory bound) | Usually 5–15MB without paid tier | Unlimited |
| Cost | Free Forever | Subscriptions ($10–$20/mo) | Paid license ($50–$200) |
| Speed | Instant client-side processing | Queued behind server uploads | Fast |
| Batch Mode | Supported with ZIP download | Usually locked behind premium | Supported |
Common Use Cases
- Job Seekers: Shrink high-resolution resumes, portfolios, and diplomas to under 2MB for job application portals.
- Business & Legal Professionals: Compact scanned contracts, tax returns, and invoices before emailing them to clients.
- Students & Researchers: Compress thesis papers, slide decks, and reading materials for submission on university learning management systems.
- Developers & Web Admins: Optimize PDF downloads on websites to reduce bandwidth usage and speed up page load times.
Frequently Asked Questions (FAQ)
Are my confidential PDF documents safe?
Yes, absolutely. Metoolzy uses modern browser technologies (WebAssembly and Canvas rendering) to process documents directly on your device. Your files are never transferred over the network to any server.
Which compression preset should I choose?
For most documents and emails, choose Recommended. It provides a 60–80% size reduction while keeping text sharp and readable. If you must meet a strict under-2MB file limit, choose Extreme. For presentations with fine graphics or text meant for printing, choose High Quality.
Will compressing my PDF remove text or make it blurry?
The tool optimizes image layers and page rendering at high DPI targets (96 to 192 DPI). Text remains crisp and easy to read.