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Compress PNG

Reduce a PNG image's file size by lowering its color precision. Upload a PNG, adjust the compression level, and download a smaller version.

Category: image
Use Case: Faster Website Loading, Storage Savings, Reducing Upload Size
Privacy: 100% browser-based

Click to upload a PNG image

Your file is processed entirely in your browser

Recommended Settings

Pro Tips

  • PNG compression is lossless, so the only way to meaningfully shrink a PNG is to reduce how much color information it contains
  • This tool reduces the number of distinct color levels per channel, which creates more repeated pixel values that PNG's compression can shrink further
  • Photos with smooth gradients show banding sooner than flat-color graphics like logos or screenshots, which often compress well even at low color levels
  • The whole file is processed locally in your browser - nothing is uploaded anywhere

Most Popular

Most users start around 64 color levels per channel and adjust down only if the file needs to be smaller

When to Use This Tool

Faster Website Loading

Shrink PNG graphics or screenshots used on a website to reduce page load times.

Storage Savings

Reduce the file size of PNG images to save storage space.

Reducing Upload Size

Shrink a PNG before uploading it somewhere with file size limits.

Simplifying Flat Graphics

Compress logos, icons, or UI screenshots that don't need full 24-bit color precision.

How It Works

1

Read the uploaded PNG file and decode it using the browser's native image support

2

Reduce each pixel's red, green, and blue values down to the selected number of levels per channel

3

Re-encode the reduced-color image as PNG using the browser's native lossless encoder

4

Compare the new file size against the original and display the percentage saved

100% Private

Files never leave your device. All processing happens locally in your browser.

Lightning Fast

Powered by Color quantization + browser native PNG encoder for optimal performance on modern browsers.

Open Source

Built with verified, open-source libraries. Fully transparent.

Frequently Asked Questions

Why doesn't a simple quality slider work for PNG like it does for JPG?

PNG is a lossless format with no adjustable quality setting - it either stores the exact pixel data or it doesn't. To meaningfully shrink a PNG, this tool reduces the number of distinct colors instead, which makes the file more compressible.

Will I see visible quality loss?

At high color-level settings (128-256), the difference is usually invisible. Lower settings can introduce visible banding, especially in smooth gradients or photographic content.

Is my image uploaded to a server?

No. The entire process runs locally in your browser using the Canvas API. Your image never leaves your device.

Does transparency still work after compression?

Yes. This tool only reduces the color precision of the red, green, and blue channels - the alpha (transparency) channel is left untouched.

What if the compressed file isn't actually smaller?

For some images, especially ones that are already simple or have few colors, reducing color levels further may not shrink the file. Try a lower level, or the image may already be close to its practical minimum size.