uDocumentViewer
Compress.pdf

Compress a PDF in your browser

100% localFiles never leave your device — no upload, no account, no tracking.
About Compress PDF

Make bulky PDFs smaller without sending them to a cloud service. This tool downsamples the embedded images and re-compresses them at a DPI and quality you choose, using mupdf compiled to WebAssembly — ideal for email attachments and upload limits.

The entire process runs in your browser. Contracts, scans, and reports stay on your device, which matters when the document is confidential.

How it works
  1. 01

    Add a PDF

    Drop your PDF file onto the page or pick it from your device.

  2. 02

    Set DPI and quality

    Choose the target image DPI and quality to control the size.

  3. 03

    Compress

    Click Compress to rewrite a smaller PDF locally with mupdf.

  4. 04

    Download

    Save the compressed PDF.

Features
downsamples imagesadjustable DPIkeeps text
Frequently asked
How does the Compress PDF compressor work?
Make bulky PDFs smaller without sending them to a cloud service. This tool downsamples the embedded images and re-compresses them at a DPI and quality you choose, using mupdf compiled to WebAssembly — ideal for email attachments and upload limits.
Are my files uploaded to a server?
No. Everything runs entirely in your browser using local JavaScript and WebAssembly. Your files never leave your device.
Does it cost anything or require an account?
No. The compressor is free, needs no sign-up, and runs locally in your browser.
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