Compress PNG Images
Shrink PNG files while keeping transparency — smart colour reduction, right in your browser.
How to compress a PNG
- Choose how many colours to keep — 256 looks identical for most screenshots, logos and graphics.
- Drop or choose your PNG files; each is quantized and re-encoded on your device.
- Check the savings and click Download.
How PNG compression works
PNG is lossless, so the biggest savings come from reducing the number of colours (quantization) and storing the image as an 8-bit palette PNG. Screenshots, logos, icons and illustrations usually look identical with 256 colours or fewer. Photos with smooth gradients compress better as JPG or WebP.
Uses the open-source UPNG.js encoder. If a file can't be made smaller, the original is kept.
Frequently asked questions
Is transparency kept?
Yes. Alpha transparency is preserved in the palette PNG.
Are my images uploaded?
No. The PNG encoder runs inside your browser; your files never leave your device.
How is this different from TinyPNG?
It uses the same idea — lossy colour quantization to an 8-bit PNG — but runs locally, with no upload limits and no account.
Why didn't my PNG get smaller?
Images that are already optimized or have very few colours may not shrink further. Try fewer colours, or convert photos to JPG/WebP.