About Compress PDF
Reduce PDF file size to exact target with precision compression
Our advanced PDF compressor uses smart algorithms to reduce file size to your exact target—100KB, 50KB, or any custom size. Unlike other tools, we compress locally in your browser for complete privacy.
How to Compress PDF
1Upload Your PDF
Select the PDF file you want to compress. Drag and drop or click to browse. Supports files up to 50MB.
2Choose Compression Mode
Select Target Size (exact KB) or Quality Preset (Extreme, Recommended, High).
3Compress & Download
Click "Compress PDF" and watch progress. Download instantly when complete.
Technical Capabilities
- Smart Target Size Compression: Utilizes binary search algorithm to iteratively find optimal quality and DPI settings that achieve your exact target file size. The system performs up to 8 compression attempts, adjusting parameters between each iteration to land within 5KB of your target.
- Dual Compression Modes: Choose between Target Size mode (specify exact KB/MB) or Quality Preset mode (Extreme, Recommended, High Quality) for different use cases. Target mode perfect for email limits; Quality mode ideal for general size reduction.
- Client-Side Processing: All PDF rendering and compression execute locally in your browser using canvas-based image conversion and JPEG quality adjustment. Zero network requests during processing—verify via browser DevTools Network tab.
- Quality Presets: Three scientifically calibrated presets—Extreme (72 DPI, 50% quality), Recommended (120 DPI, 70% quality), High Quality (150 DPI, 85% quality)—balance file size reduction with visual fidelity for common use cases.
- Complete Privacy Guarantee: No cookies, no localStorage, no IndexedDB usage. File data cleared from JavaScript heap memory upon download or page reload. Browser cache contains only transient canvas render data, automatically purged on session end.
Professional Use Cases
Email Attachment Optimization
Compress large PDFs to meet email server attachment limits (typically 10MB, 25MB, or specific KB requirements). Ensure contracts, proposals, and reports can be sent without file compression warnings or delivery failures.
Online Form Submissions
Meet strict file size requirements for job applications, grant submissions, government portals, and university applications that enforce 100KB, 200KB, or 500KB upload limits for supporting documents.
Web Performance Optimization
Reduce PDF sizes for embedded documents on websites, improving page load times and user experience. Essential for document-heavy sites, intranets, and knowledge bases where bandwidth matters.
Cloud Storage Savings
Reduce document storage footprint in cloud services like Google Drive, Dropbox, or OneDrive. Compress archived documents to maximize available storage space without losing document accessibility.