> ## Documentation Index
> Fetch the complete documentation index at: https://compresto.app/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# How to compress PDF

> Reduce PDF file size for easier sharing and storage

<Warning>
  PDF compression requires **Ghostscript** to be installed on your Mac. Compresto will automatically detect if Ghostscript is missing and show an alert when you select PDF files. See the [installation guide](/guides/getting-started/install-ghostscript) for setup instructions.
</Warning>

## Quick Start

<Steps>
  <Step>
    Click on the selection panel to select PDFs, or drag and drop PDFs/folders into it

    <img src="https://mintcdn.com/compresto/Z4FNL_2JKBxzG7XW/images/image.png?fit=max&auto=format&n=Z4FNL_2JKBxzG7XW&q=85&s=c320f0b188a96e1453d412a87bb20756" alt="select pdfs" width="2022" height="1574" data-path="images/image.png" />
  </Step>

  <Step>
    Select the PDF quality level

    <img src="https://mintcdn.com/compresto/Wyt9cxDElTiY283z/images/CleanShot2025-12-29at11.10.10@2x.png?fit=max&auto=format&n=Wyt9cxDElTiY283z&q=85&s=a4af78fdacc5fd68fa75001d97cd70b3" alt="pdf options" width="1962" height="1570" data-path="images/CleanShot2025-12-29at11.10.10@2x.png" />
  </Step>

  <Step>
    Press **Compress** to start

    <img src="https://mintcdn.com/compresto/Wyt9cxDElTiY283z/images/CleanShot2025-12-29at11.10.10@2x.png?fit=max&auto=format&n=Wyt9cxDElTiY283z&q=85&s=a4af78fdacc5fd68fa75001d97cd70b3" alt="compress" width="1962" height="1570" data-path="images/CleanShot2025-12-29at11.10.10@2x.png" />
  </Step>

  <Step>
    View compression results and open files in Finder

    <img src="https://mintcdn.com/compresto/Wyt9cxDElTiY283z/images/CleanShot2025-12-29at11.11.01@2x.png?fit=max&auto=format&n=Wyt9cxDElTiY283z&q=85&s=96f36f91aab0cd3cd0f5c83a3eb4b34b" alt="results" width="1946" height="1530" data-path="images/CleanShot2025-12-29at11.11.01@2x.png" />
  </Step>
</Steps>

## Quality Options

| Quality     | Description                                | Best For                         |
| ----------- | ------------------------------------------ | -------------------------------- |
| **Best**    | Highest quality, preserves all details     | Professional printing, archiving |
| **High**    | High quality suitable for printing         | Office printing                  |
| **Balance** | Good balance of quality and size (default) | Email attachments, web sharing   |
| **Low**     | Maximum compression, screen viewing only   | Quick sharing, previews          |

## What Each Quality Level Does

### Best (Prepress)

* Preserves maximum image quality
* Keeps high-resolution images
* Maintains color accuracy
* Best for: Print production, archival copies

### High (Printer)

* Optimized for standard printing
* Good image quality
* Reasonable file size reduction
* Best for: Office documents, reports

### Balance (eBook)

* Optimized for screen viewing
* Moderate image compression
* Significant file size reduction
* Best for: Email, web uploads, sharing

### Low (Screen)

* Maximum compression
* Lower image resolution
* Smallest file sizes
* Best for: Quick previews, bandwidth-limited sharing

## Tips for Best Results

* **For email attachments**: Use "Balance" quality to stay under size limits
* **For printing**: Use "High" or "Best" quality
* **For web uploads**: Use "Balance" for fast loading
* **For archiving**: Use "Best" to preserve document quality
* **For quick sharing**: Use "Low" when quality isn't critical