📦 PDF Compressor — Reduce PDF File Size
Compress and optimize PDF documents by removing unused objects, metadata, and downsampling images. All processing happens in your browser.
How to Compress a PDF
Drop a PDF file onto the converter above. Select your desired compression level — Low for quick cleanup, Medium for balanced reduction, or High for maximum compression. Optionally remove metadata to save extra space. Click "Compress PDF" and download your optimized file.
The compression process removes unused objects, redundant data streams, and optionally strips author, title, and other metadata fields. At higher levels, images are downsampled via Canvas to reduce resolution while maintaining readability.
Compression Levels Explained
Low: Removes unused objects and dead references within the PDF structure. Safe for all documents with no visible change. Typically saves 5-15%.
Medium: Removes unused objects and optionally strips metadata. Removes empty pages and redundant stream data. Saves 15-35% on most documents.
High: All medium optimizations plus image downsampling. Images are scaled down via Canvas to reduce resolution. Saves 30-60% on image-heavy PDFs.
Compression Level Comparison
| Level | Unused Objects | Metadata Removal | Image Downsampling | Typical Savings |
|---|---|---|---|---|
| Low | Yes | Optional | No | 5-15% |
| Medium | Yes | Optional | No | 15-35% |
| High | Yes | Optional | Yes (Canvas) | 30-60% |
Compressed PDF vs Original — Pros and Cons
Compressed PDF vs Original PDF
Pros of Compression: Smaller file size for email and storage, faster upload/download times, reduced bandwidth usage, compatible with all PDF readers.
Cons of Compression: Image quality may decrease at high levels, metadata loss when removed, processing time increases with file size.
Lossless vs Lossy Compression
Lossless (Low/Medium): No visible change to content. Safe for text documents, forms, and vector graphics. Removes only redundant PDF structure data.
Lossy (High): Image downsampling reduces pixel count. Best for image-heavy PDFs where small quality loss is acceptable for significant size reduction.
Metadata Removal Benefits
Pros: Reduces file size by stripping author, title, subject, and creator fields. Enhances privacy by removing document authorship information.
Cons: All metadata is permanently removed. If you need to preserve document properties, uncheck the remove metadata option.