PDF Compressor

About this tool

Most of a PDF's file size comes from embedded images and internal bloat (uncompressed object tables, duplicated resources, editor metadata). This tool offers two honest strategies rather than a magic "compress" button that quietly does one or the other:

Optimize structure rebuilds the file's internal object streams and cross-reference tables in their most compact form without touching a single pixel of any image or a single character of text. It is lossless — text stays selectable, vector graphics stay sharp — and it's the right choice whenever the PDF must remain fully faithful to the original. Savings depend entirely on how much internal bloat the source file had; a PDF already exported by an efficient tool may shrink very little.

Recompress as images renders every page to a JPEG at the resolution and quality you choose, then assembles a brand-new PDF from those page images. This is a real trade-off, not a trick: because every page becomes a flat image, text is no longer selectable, searchable, or copyable, and very fine text or line art can look softer at low resolution or low quality. In exchange, it usually produces the biggest size reduction by far, especially for scanned documents or image-heavy files — lower the resolution and quality sliders for maximum shrinkage, or raise them if the result looks too soft.

Both modes run a live before/after comparison of page 1 and report the exact size change — including telling you plainly if a given file barely shrinks or even grows slightly, which can happen with structure-only optimization on a file that was already well-optimized. Everything happens locally using pdf.js and pdf-lib running in your browser; your PDF is never uploaded anywhere.