Compress PDF online — shrink file size without uploading

Reduce large PDFs to email-friendly size in seconds, entirely in your browser. No upload, no watermark, no sign-up wall — with a downloadable receipt proving your file never left your device.

Open the free tool →

Most online PDF compressors send your document to a server, add a watermark, or ask for your email first. Kameleo does none of that. The compression runs locally with WebAssembly, so a confidential contract, ID scan, or medical report is optimized on your machine and nowhere else.

Pick how hard to squeeze — from a light pass that keeps text razor-sharp to an aggressive setting for the smallest possible file — then download. Nothing is uploaded, so there is no server-side copy to leak, and you can confirm it yourself in your browser's Network tab.

100% on your device

Your PDF is compressed in the browser. No upload, no cloud storage, no server-side copy to leak or subpoena.

Quality you control

Choose the compression level. Keep images crisp for print, or go smaller for email — you decide the trade-off.

No watermark, no wall

Free downloads are clean. No stamped logo, no forced account, no email capture before you get your file.

Proof, not promises

Download a privacy receipt with SHA-256 hashes computed locally — evidence the bytes never left your device.

How to compress pdf in three steps

  1. Drop your PDF onto the page (or click to browse). It loads straight into your browser — no upload.
  2. Choose a compression level. Kameleo shows the estimated size so you can balance quality and weight.
  3. Click Compress, then download your smaller PDF — and optionally a privacy receipt proving it stayed on your device.

Frequently asked questions

Is compressing PDFs here really free?

Yes. Compression is free with a generous daily limit and a 50 MB per-file cap on the free plan. There is no watermark and no account required to download.

Do my files get uploaded to a server?

No. The entire process runs in your browser with WebAssembly. You can open your browser's Network tab and watch — no file bytes are sent anywhere.

Will compression ruin the quality?

You control the trade-off. A light pass keeps text and vector graphics perfectly sharp and mainly re-optimizes images; a stronger pass trades some image fidelity for a much smaller file.

How small can the file get?

It depends on the source — scanned, image-heavy PDFs shrink the most (often 50–80%), while PDFs that are mostly text are already compact and change less.

Is there a file-size or page limit?

The free plan handles files up to 50 MB. Larger files and higher daily volume are available on a paid plan, still processed entirely on your device.

Does it work on mobile?

Yes. Kameleo runs in any modern mobile browser — no app install needed — and the file still never leaves your phone.

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