Online Document Compressor
Drop any document — PDF, Word, PowerPoint, or Excel — and our engine will automatically optimize embedded images, remove metadata, and reduce file size while preserving layout and formatting.
Drop any document here — we auto-detect the format
Max 100MB per file • No signup required
How It Works
Upload Images
Drag and drop or click to select image files. We support JPG, PNG, WebP, GIF, and more.
Choose Settings
Pick a quality preset — Lossless, Recommended, or Extreme — and optionally resize for web.
Download
Get compressed files instantly. Download individually or all at once as a ZIP archive.
Frequently Asked Questions
Will compressing a PDF affect text quality?
Can I compress scanned PDFs?
Will my Word document formatting be preserved?
Document Compression: PDF Optimization, Office Files & Best Practices
Document compression reduces the file size of PDFs, Word documents, presentations, and spreadsheets. Large documents are one of the most common causes of email attachment failures and slow cloud uploads.
Why Documents Get So Large
The primary culprit in large documents is embedded images. A single high-resolution photo in a Word document can add 5-10MB. PDFs created from scanners often contain full-resolution page images at 300+ DPI. Presentations with many slides and media can easily reach 50MB or more.
How Document Compression Works
- Image recompression: The biggest win. Embedded images are re-encoded with optimized quality settings — often reducing them by 60-80% with no visible difference on screen.
- Metadata removal: Document properties, revision history, comments, and hidden data are stripped.
- Font subsetting: Instead of embedding entire font files, only the characters actually used are included.
- Object optimization: Duplicate objects, unused resources, and redundant data structures are consolidated or removed.
Format-Specific Tips
PDF files benefit the most from compression because they often contain multiple high-resolution images and redundant object streams. A 50MB scanned PDF can often be reduced to 5MB.
DOCX/PPTX/XLSX files are actually ZIP archives containing XML and media files. Compression optimizes the media inside while preserving the XML structure that defines formatting.
EPUB e-books are also ZIP-based. Optimizing cover images and chapter illustrations can significantly reduce download time for readers.
How MiCompress Handles Documents
Our engine detects the document type and applies format-specific optimization. For PDFs, we use advanced recompression with quality-aware settings. For Office documents, we decompress the ZIP container, optimize all media assets, and repackage. All text, formatting, and layout are preserved exactly.