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PDF Compressor

Compress PDF in your browser — no upload, free, unlimited

Privacy: this tool runs entirely in your browser — files are never uploaded, and data is gone when you close the page.

How to use

  1. Click the dashed box (or drag & drop) to select the PDF you want to compress.
  2. Click "Compress now" — the tool re-encodes the PDF with object streams right in your browser.
  3. The compressed file downloads automatically with a before/after size comparison.

FAQ

Will my file always get smaller?

Most digitally-created PDFs shrink noticeably, but the ratio depends on the internal structure. Scanned PDFs gain little because pages are already full-page images.

Is my file uploaded anywhere?

No. Compression happens entirely inside your browser; the file never leaves your computer and works offline.

Any limits?

No usage limits. File size is only bound by browser memory — keeping files under 100MB is recommended.

About this PDF Compressor

This tool uses the client-side pdf-lib engine to losslessly re-encode your PDF, shrinking file size through object streams and structural optimization — no server involved. Text-and-vector PDFs compress well; scanned (image-based) PDFs have limited gains since each page is already a picture.