# Compress PNG Files, Keep Transparency

Make PNG screenshots, icons and logos much smaller while staying PNG, with transparent areas intact. Choose how many colours to keep and compare the sizes.

_Source: https://sharelargefilesfree.com/tools/compress-png · Updated 2026-09-29_

## How to use it

1. Choose your PNG files.
2. Keep 256 colours (recommended), or pick fewer for even smaller files.
3. Press Compress PNGs.
4. Compare before and after, then download or send them.

## Why PNGs are big, and how this shrinks them

A PNG normally stores up to 16 million colours per pixel and never throws anything away. For screenshots, charts, logos and illustrations that is wasteful: they rarely use more than a few hundred distinct colours. This tool analyses each image, picks the best palette of up to 256 colours and maps every pixel to it, including partly transparent pixels. The resulting PNG is typically 50 to 80 percent smaller and still a normal PNG that works everywhere.

## Choosing the number of colours

- **256** is right for almost everything; the difference is invisible on screenshots and flat graphics.
- **128 or 64** gives smaller files for simple icons and diagrams.
- **All colours (lossless)** re-saves without reducing colours. It helps less, but keeps every pixel identical.

Photos saved as PNG are the exception: smooth gradients can show banding with a palette. For photos, a JPG or WebP is far smaller anyway; see [PNG to JPG](https://sharelargefilesfree.com/tools/png-to-jpg) or [Compress image](https://sharelargefilesfree.com/tools/compress-image).

## Transparency stays transparent

Unlike converting to JPG, compressing a PNG keeps its transparent background, so logos and cut-out product images still sit cleanly on any page colour. The work happens in your browser; your files are not uploaded.

## Frequently asked questions

### Is PNG compression lossless?

The recommended setting reduces colours to a palette, which is technically lossy but usually invisible. Choose “All colours” for a fully lossless re-save.

### Will transparency be kept?

Yes, including soft edges and partly transparent pixels.

### How much smaller will my PNG get?

Screenshots and graphics usually shrink by 50 to 80 percent at 256 colours. Photos saved as PNG shrink less and are better converted to JPG.

### Are my files uploaded?

No. Compression happens on your device.