# Compress a PDF to a smaller file size

Source: https://www.mergevanta.com/compress-pdf
Updated: 2026-10-22

> Compress PDF online free with no watermark and no sign-up. Shrink PDF file size for email and uploads while text stays sharp — files are never stored.

Make a PDF smaller for email, uploads and sharing. Pick how much to compress: images are resampled while text and drawings stay sharp. It's free, with no watermark and no sign-up, and your files are never stored.

## How do I reduce the size of a PDF for free?

Open Mergevanta's Compress PDF tool, add your file and pick a level: Less compression, Recommended or Extreme. Images are resampled and re-encoded, fonts are trimmed and unused data is removed, while text stays sharp and selectable. You see the size before and after, with no watermark or sign-up.

## Key facts

- **Price:** Free
- **Watermark:** None
- **Sign-up:** Not required
- **Accepts:** .pdf
- **You get:** A smaller .pdf
- **Processing:** Encrypted server for files up to 4 MB, your browser for larger ones
- **Files stored:** Never
- **Works on:** Windows, macOS, Linux, iPhone, iPad and Android

## Why use Mergevanta

- **Text stays sharp:** Only images are resampled and re-encoded. Text and vector drawings are never turned into pictures, so they stay crisp and searchable.
- **Three clear levels:** Choose high quality, the balanced Recommended setting or the smallest file, then see exactly how much you saved.
- **Big files welcome:** Files up to 4 MB are compressed on our server; larger ones are compressed right in your browser, so there's no upload cap.
- **Private and free:** No watermark and no sign-up. Uploads are encrypted end to end, processed in memory and deleted straight away.

## How to use it

1. Click Choose PDF, or drop your file onto the page.
2. Pick a level: Less compression · high quality, Recommended or Extreme · smallest file.
3. Open More options to convert to grayscale, remove metadata or flatten form fields, if you want.
4. Press Compress PDF and check the before and after sizes.
5. Press Download to save the smaller PDF.

## Frequently asked questions

### Where is my PDF compressed?

Files up to 4 MB are sent to Mergevanta's server encrypted end to end, compressed in memory and deleted as soon as the result is sent back. Larger files are compressed in your browser and never leave your device.

### Will compressing reduce the quality?

Text, fonts and vector drawings keep their exact quality. Only images change: they're resampled to about 220, 150 or 96 dots per inch, depending on the level, and saved as JPEG. Choose Less compression if you plan to print.

### Why didn't my PDF get smaller?

Some PDFs are already compact, such as text-only files or ones exported with small images. When compressing wouldn't save at least 1%, Mergevanta keeps your original file and tells you it's already well compressed.

### Can I compress a password-protected PDF?

Yes. Enter the password when asked and the file is compressed as usual. The compressed copy has no password, so add one again with [Protect PDF](https://www.mergevanta.com/protect-pdf) if you need it.

### Is there a file size limit?

There's no fixed limit. Files up to 4 MB go to the server; bigger files are compressed in your browser, limited only by your device's memory. Very large files can take a minute or two.

### What do grayscale and flatten do?

Grayscale turns colored text, drawings and images gray, which saves the most on color scans. Flattening fixes form answers into the page so they can no longer be changed.

### Can I compress a PDF on my phone?

Yes. Compress PDF works in mobile browsers on iPhone and Android, with no app to install.

## Related tools

- [Merge PDF](https://www.mergevanta.com/merge-pdf)
- [Split PDF](https://www.mergevanta.com/split-pdf)
- [Protect PDF](https://www.mergevanta.com/protect-pdf)