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Compress PDF

Shrink a PDF for email or upload without turning text into an image — pick a level, see the new size, keep every letter selectable.

0 B uploaded to any server

Most of the weight in a PDF is images, not text. A 40-page report can be 200 KB; the same report with photos pasted in from a phone can be 60 MB, because each photo is stored at 12 megapixels even though it prints at postcard size. Compression here runs Ghostscript compiled to WebAssembly, which downsamples images to a sensible target resolution, re-encodes them and rebuilds the file's object structure.

Because it is real Ghostscript rather than a re-save, the result is predictable: text and vectors are untouched and stay sharp at any zoom, and the saving comes entirely from the raster content. On a document that is already text-only there is little to gain, and the honest outcome is a file close to the original size.

How it works

  1. Open the PDF you want to shrink.
  2. Pick a quality level — lighter settings downsample images more aggressively.
  3. Compress, then compare the resulting size against the original.
  4. Download it, or try a different level if the trade-off isn't right.

What people use it for

  • Getting a scanned contract under a 10 MB email attachment limit.
  • Reducing a photo-heavy portfolio before uploading it to a portal that rejects large files.
  • Shrinking scans archived at 600 dpi that only ever need to be read on screen.

Frequently asked questions

Is my file uploaded to a server?
No. The file is opened by JavaScript and WebAssembly running inside your own browser tab. It is never uploaded, there is no server-side processing and nothing is stored — closing the tab discards everything.
Why did my file barely shrink?
Because it was probably already efficient. Compression works on images; a PDF exported from Word that contains only text and vector shapes has almost nothing to remove. If the file is large and text-only, it is usually font embedding or an unusual generator, and Linearize or Repair may help more.
Will the text get blurry?
No. Text and vector graphics are copied through unchanged and remain resolution-independent. Only raster images are downsampled, which is where visible quality loss can appear at the strongest settings.
Should I compress a document before printing it?
Generally no. Print benefits from the original image resolution. Compress for email, upload and screen reading; keep the original for the printer.

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