Free PDF Compressor - Reduce PDF File Size

Shrink PDF bytes in your browser with pdf-lib. Local processing, before/after size stats, and no upload to WebTooly.

About PDF Compressor

`pdf-lib` reload + `save({ useObjectStreams: true, addDefaultPage: false })` after `PDFDocument.load(arrayBuffer, { ignoreEncryption: true })`. This re-serializes the PDF; it is **not** a per-image JPEG recompression pipeline.

How it works (technical)

Savings depend on redundant structure in the source—some files shrink, some barely change.

Embedded photos are not batch re-encoded at a new quality; for that, use desktop prepress or extract/recompress images.

Encrypted PDFs usually fail until decrypted elsewhere.

UI shows original vs output `Blob.size`.

When to use it

  • Verbose exports

    CAD or print pipelines that emit bloated object graphs may shrink on re-save.

  • Under upload caps

    Try a smaller byte size before submitting to a portal.

  • Quick check

    See whether a simple client-side pass helps your specific file.

How to Use PDF Compressor

  1. 1Upload your PDF file by dropping it or clicking to browse.
  2. 2Click "Compress PDF" to optimize your document.
  3. 3View the compression statistics showing size reduction.
  4. 4Download the compressed PDF with reduced file size.

Key Features

  • `save` with `useObjectStreams`
  • Before/after bytes
  • Standard PDFs; encryption often blocks load
  • Local download

Benefits

  • Honest size readout
  • Client-side only
  • No rasterization step

Frequently Asked Questions

How much can I compress my PDF?

Compression results vary depending on the original PDF content. Text-heavy documents typically compress more than image-heavy ones, with reductions of 10-50% common.

Will compression affect PDF quality?

This flow re-saves the PDF with pdf-lib; visible quality is usually unchanged. How much smaller the file gets depends on the original—some PDFs shrink a lot, others only a little.

Can I compress password-protected PDFs?

Encrypted or password-protected PDFs cannot be compressed with this tool. You'll need to remove the password protection first.

Is my data safe?

Yes, all processing is done locally in your browser.

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