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FlexibleToolsAI
Browser Engine · 100% Client-Side Private

Compress PDF

Reduce the size of large, scanned or image-heavy PDFs so they're easy to email and upload. Everything runs in your browser — your document is never uploaded.

To compress a PDF, add your file, pick a compression level, click Compress, and download the smaller PDF — processed entirely in your browser with no upload.

Accepts PDFZero Uploads

Drop your files here, or choose files

Supports up to 100 MB per file · Batch convert multiple files at once

Tip: PressCmd + Vto paste images

Zero Server Uploads

Files process in local RAM

Instant WASM Speed

No waiting queues or lags

Unlimited Batching

Convert files without limits

How to use Compress PDF

  1. 1Add the PDF you want to shrink.
  2. 2Choose a compression level and image quality.
  3. 3Click Compress PDF; each page is re-rendered and rebuilt locally.
  4. 4Check the before/after size, then download the compressed PDF.

How it works

Add your PDF, choose a compression level and quality, and each page is re-rendered as a compressed image and rebuilt into a smaller PDF — all on your device. You'll see the before and after sizes for each file.

This approach is especially effective on scanned documents and PDFs full of photos.

What to expect

Because compression works by rasterising each page, the text in the output becomes part of the page image and is no longer selectable or searchable. That's the trade-off for the size reduction, and it's why this is ideal for scans rather than text documents.

For text-only PDFs that are already small, compression may not help — the tool shows “no gain” honestly rather than producing a larger file you didn't want.

Why compress locally

Uploading a confidential PDF to a compression service defeats the point of keeping it private. Here the document never leaves your device.

Lower the quality slider or pick a stronger compression level for smaller files; raise them to keep more detail.

Frequently Asked Questions

Are my images uploaded to a server?

No. Every conversion runs locally in your browser using your device's own processor. Your images never leave your computer or phone, and nothing is stored on our servers.

Will the text still be selectable after compressing?

No. This tool compresses by rendering each page to an image, so text becomes part of that image. It's designed for scanned and image-heavy PDFs where size matters more than selectable text.

How much smaller will my PDF get?

It depends heavily on the content. Scanned and photo-heavy PDFs often shrink dramatically; PDFs that are already just compact text may not shrink much, and the tool will tell you honestly.

Is there a file size limit?

The practical limit is your device's memory rather than a fixed cap. Very large documents use more RAM because each page is rendered before being re-encoded.

Is it free, and are there limits?

It's completely free with no account required. Because processing happens on your device, there's no per-file upload limit — the practical ceiling is your device's available memory. You can batch many files and download them as a single ZIP.

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