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PDF Compressor - Reduce PDF Size - Comprimir PDF - PDF Compress

Compress PDF files instantly without losing quality. Reduce file size for email, web upload, or storage using a powerful browser-based compression engine with multiple quality presets.

Instant Compression Quality Presets Free & Secure

Key Features

Advanced Compression Engine

Industry-standard PDF optimization running locally in your browser via WebAssembly. Desktop-grade compression quality with complete privacy.

4 Quality Presets

Choose from Screen (smallest), eBook (balanced), Printer (high quality), or Prepress (maximum quality). Find the perfect balance between size and quality.

Size Savings Display

See exactly how much space you saved with before/after file size comparison and percentage reduction. Know your compression results instantly.

100% Browser-Based

All compression happens locally in your browser. Your PDF files are never uploaded to any server. Complete privacy and security guaranteed.

Progress Tracking

Real-time progress bar shows compression status from file reading through compression to completion. Never wonder if it's still working.

Up to 100MB Files

Compress PDFs up to 100MB in size. Handles large documents, presentations, ebooks, and scanned files with ease. Optimized for memory efficiency.

How to Compress a PDF

1
Upload PDF

Drag & drop your PDF file or click to browse. Supports files up to 100MB. Only one file at a time for optimal compression.

2
Choose Quality

Select from 4 presets: Screen (72 DPI), eBook (150 DPI), Printer (300 DPI), or Prepress (maximum quality). Higher quality = larger file.

3
Compress

Click "Compress PDF" to start. The compression engine processes your file locally with real-time progress tracking.

4
Download

See the size reduction percentage and download your compressed PDF. Compare original vs compressed file sizes instantly.

Why Choose Our PDF Compressor?

  • No Registration Required - Start compressing PDFs immediately
  • WebAssembly Engine - Desktop-grade compression in browser
  • 4 Quality Levels - Screen, eBook, Printer, and Prepress presets
  • Up to 100MB - Handle large PDF documents with ease
  • 100% Browser-Based - Files never leave your device
  • Real-Time Progress - See compression status as it happens
  • Size Comparison - Before/after with percentage savings
  • Memory Efficient - Optimized for large file processing

Frequently Asked Questions

Our tool uses a professional PDF optimization engine compiled to WebAssembly (WASM) running directly in your browser. It optimizes images, fonts, and PDF structure based on your chosen quality preset. Screen (72 DPI) produces the smallest files, eBook (150 DPI) balances quality and size, Printer (300 DPI) maintains high quality, and Prepress preserves maximum quality.

Screen (72 DPI): Best for email attachments and web sharing. Smallest file size.

eBook (150 DPI): Good balance for digital documents and e-readers.

Printer (300 DPI): High quality for printing and professional use.

Prepress: Maximum quality preservation for commercial printing.

Yes! All compression happens entirely in your browser using WebAssembly. Your PDF files are never uploaded to any server. The compression engine runs locally on your device. We cannot see, access, or store your files. Your documents remain completely private.

The tool supports PDF files up to 100MB in size. For best performance with large files, we recommend using the Screen or eBook quality presets which process faster. The compression engine is optimized for memory efficiency to handle large documents smoothly.

Size reduction depends on the original PDF content and chosen quality preset. Screen quality typically achieves 60-80% reduction for image-heavy PDFs. Text-based PDFs may see smaller reductions. After compression, you'll see the exact before/after sizes and percentage saved.

Compression time varies based on file size, content complexity, and your device's processing power. Small files (under 10MB) typically compress in seconds. Larger files (50-100MB) may take 30-60 seconds. The real-time progress bar keeps you informed throughout the process.

Quality impact depends on the preset you choose. Prepress and Printer maintain near-original quality. eBook provides a good balance. Screen quality reduces image resolution significantly for maximum size savings. Text content remains sharp at all quality levels.

Yes! Our PDF Compressor is fully responsive and works on all devices. However, compression is CPU-intensive and works best on desktop. Mobile devices can compress smaller files, but larger files may take longer due to processing limitations.

Ratings & Reviews

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