About Compress PDF

Under the hood, our compressor runs your file through Ghostscript, the same engine professional print shops and publishers rely on, using one of three quality presets. Low uses Ghostscript's /screen setting — images get downsampled hardest, so text-heavy office documents and scanned pages shrink the most, but photos lose some sharpness. Medium (/ebook) is the balanced default most people want: noticeably smaller with no visible change on a screen. High (/prepress) barely touches image quality at all, which means it also barely reduces file size — it exists for documents where preserving photo or scan detail matters more than shaving off megabytes.

If Ghostscript is ever unavailable on the server, the tool automatically falls back to rebuilding the PDF page-by-page, which still strips out redundant internal objects and shrinks the file, just less aggressively than the Ghostscript path. Either way, nothing about the page count, text, or vector graphics changes — only the raster image data is affected.

Key Features

• Ghostscript-powered compression with three real presets: Low (/screen, smallest file), Medium (/ebook, balanced), High (/prepress, best image quality)
• Automatic fallback compression if Ghostscript is unavailable, so the tool never simply fails
• Text and vector graphics are never touched — only raster images are downsampled
• Works on any page count — compress 500-page PDFs in seconds
• Files up to 50 MB, no account or registration required