# How to compress a PDF on Android offline

> To compress a PDF on Android offline, open the file in Scanly's Compress tool, choose High, Balanced or Smallest, check the before and after size, and save the smaller copy. Scanly compresses the file on your phone and leaves the original unchanged.

A scanned PDF can easily reach several megabytes, which is too large for some email limits, upload forms and messaging apps. Compressing it reduces the file size, usually by lowering image quality.

Scanly's Compress tool is one of its offline PDF tools. It works without an internet connection and does not upload your document, so the file stays on your phone while you shrink it.

## How to compress a PDF on Android offline

1. **Get the PDF into Scanly.** Open the PDF with Reader, or choose "Open in Scanly" from Files, Gmail, WhatsApp or Google Drive.
2. **Open the Compress tool.** Open the Compress tool in Scanly's PDF tools.
3. **Choose a level.** Select High, Balanced or Smallest, depending on how small the file must be.
4. **Compare the sizes.** Look at the before and after size that Scanly shows. If the result is too blurry to read, go back and choose a higher level.
5. **Save the smaller file.** Save or share the compressed PDF. The original file is left as it was.
6. **Merge or protect if needed.** If you need to combine files first, use Merge. If the result must be protected, use the Password tool.

## Choosing a compression level

- High: usually keeps the most detail, with the smallest reduction.
- Balanced: a middle option that suits most documents.
- Smallest: the greatest reduction, which can visibly soften images and fine text.
- Check the result: Scanly shows the before and after size, so you can pick the level that meets your limit.

## Other PDF tools that help

If you have several files, use Merge first to combine them into one PDF, then compress that single file. To protect the result, use the Password tool to add an open password with AES-256 encryption or to restrict editing.

## Your original stays the same

Compression writes a new, smaller file. Scanly never changes the original, so you can keep the full-quality copy for printing or archiving and send only the smaller one.

## Frequently asked questions

### How do I compress a PDF on Android without uploading it?

Open the PDF in Scanly, use the Compress tool, choose High, Balanced or Smallest, and save the result. Compression runs on your phone, so nothing is uploaded.

### Which compression level should I choose?

Start with Balanced. Use High when text and images must stay sharp, and Smallest only when the file must be as small as possible. Scanly shows the before and after size so you can compare.

### Does compressing a PDF reduce its quality?

It can. Compression usually lowers image quality, and the Smallest level may soften fine text or detail. Open the compressed file and check it before you send it.

### Will compression change my original PDF?

No. Scanly saves a smaller copy and leaves the original file unchanged.

### Can I merge PDFs before compressing them?

Yes. Scanly's Merge tool combines PDFs offline, so you can compress one file instead of several.

Get Scanly free on Google Play: https://play.google.com/store/apps/details?id=in.c1ph3rj.scanly

Last checked: 2026-10-22. Canonical: https://www.usescanly.co.in/compress-pdf-android