Compress your PDFs quietly

Drop one PDF or many. Your files never leave the browser tab.

Drag & Drop PDFs here

or click to browse — pick one file or many

Max size: limited only by browser RAM

Local Vault (Recent Compressions)

Auto-clears after 2 hours

No local history found.

Compressed PDFs land here automatically and auto-clear after 2 hours.

Compress PDF Online — Free, Private, In Your Browser

QuietPDF is a free, private PDF compressor that runs entirely in your browser — your files never leave your device. Drop in one PDF or many, pick a compression level, and download smaller PDFs in seconds, with no signup and no watermarks. Compressing is just the start — it’s part of a growing set of private, in-browser PDF tools.

Why compress PDFs with QuietPDF

  • 100% private

    Files are compressed in your browser. Nothing is uploaded to a server, ever.

  • Batch compression

    Drop multiple PDFs at once and download each one individually — or all of them with one click.

  • Three quality presets

    Lossless for archives, Balanced for everyday docs, Extreme for email-attachment limits.

  • Fast & offline-friendly

    Once loaded, the page works offline. Compression happens on your own device.

  • No watermarks, no signup

    Output PDFs are clean — same content, smaller size. No accounts, no email needed.

  • Local vault

    Recent compressions live in your browser for 2 hours, then auto-clear. Wipe early any time.

How to compress a PDF online

  1. 1

    Drop your PDFs

    Drag one PDF or many onto the upload zone, or click to browse.

  2. 2

    Pick a preset

    Choose Lossless, Balanced, or Extreme — applied to every file in the batch.

  3. 3

    Download

    Compressed PDFs are ready in seconds. Download each one, or all at once.

Trying to hit a specific target — say, getting a scan under an email attachment limit? See our guide to reducing PDF file size.

More free PDF tools

Frequently asked questions

What is QuietPDF?

QuietPDF is a free, private PDF toolkit that runs entirely in your browser — starting with PDF compression, with more tools (like text extraction) on the way. Every tool works without uploading your file: nothing is sent to a server, there's no signup, and no watermarks are added.

How do I compress a PDF online for free?

To compress a PDF online for free, drag it onto QuietPDF (or pick several at once), choose a compression level — Lossless, Balanced, or Extreme — and click Compress. The smaller file downloads to your device, and the whole process runs in your browser, so there are no server uploads and no signup required.

Is QuietPDF free to use?

Yes. QuietPDF is 100% free, with no signup, no watermarks, no daily limits, and no email harvesting. Compress as many PDFs as you want.

Is it safe to compress my PDFs here?

Yes. Your files never leave your browser tab. Everything happens locally on your device — we can’t see your PDFs, store them, or send them anywhere. That’s the whole point of QuietPDF.

Can I compress multiple PDFs at once?

Yes. Drop several PDFs into the upload zone and QuietPDF will compress them one by one (to stay gentle on your browser’s memory). When the batch is done you can download each PDF individually, or hit "Download All" to grab the whole set.

What’s the difference between Lossless, Balanced, and Extreme?

Lossless preserves perfect image quality and only strips redundant metadata. Balanced downsamples embedded images to 150 DPI at 80% quality — best overall savings for everyday documents. Extreme pushes images to 90 DPI at 50% quality for the smallest possible files (great for email attachment limits).

Does QuietPDF work offline?

Once the page has loaded, yes. Compression runs entirely in your browser — you can disconnect from the internet and the tool will still work.

Does QuietPDF add a watermark to compressed PDFs?

No. Compressed PDFs come out clean — same content, smaller size. No watermark, no branding stamped on your file.

How much can QuietPDF reduce a PDF’s size?

QuietPDF can typically reduce an image-heavy PDF — scanned pages, screenshots, or photos — by 50–80% with the Balanced preset, and even more with Extreme. PDFs that are mostly text or vector graphics shrink more modestly, since there is less image data to compress.

Built for privacy

No file uploadsYour PDFs never leave the browser tab.
Local compressionCompression runs on your device.
Local storage onlyRecent compressions live in your browser for 2 hours, then auto-clear.

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