Compress and optimize PDFs online free — reduce file size with quality slider, optimize PDF structure by removing redundant data. All processing in your browser. Also: PDF Editor | Security | OCR | Utilities.
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Optimization options:
Compress: Basic compression is applied by enabling object streams and removing unused objects. Compression level adjusts object stream settings. Expected reduction: 5-20%. For larger reductions, use a server-side tool. Quality is not affected.
Optimize: Object streams combine small objects for better compression. Linearization enables fast web viewing (byte-at-a-time loading). These optimizations change internal PDF structure without affecting visual content.
Why the reduction is often modest: text and vector content in a PDF is almost always already Flate-compressed (the same family of algorithm as ZIP), so re-packing objects only trims structural overhead. In scan-heavy files, the images are where the bytes live — real savings there require downsampling or re-encoding images, which changes visual quality and needs a server-side tool. See how a PDF is structured inside.
