Is transparency kept?

Yes. Transparent and semi-transparent pixels are preserved.

Should I use PNG or JPG for photos?

Photos are usually far smaller as JPG or WebP. Use PNG for screenshots, graphics, text and anything that needs transparency. The Compress image tool can convert between formats.

Are my files uploaded to a server?

No. This tool runs entirely inside your browser using JavaScript. Your files are read from your device, processed in memory, and the result is handed straight back to you as a download. Nothing is transmitted, stored or logged, and the page keeps working if you go offline after it has loaded.

Is it really free? Are there watermarks or limits?

Yes, it is free with no signup, no watermark and no daily quota. Because the work happens on your own device, there is no server cost that would force limits. The only practical limit is your device's memory, which matters for very large files.

Compress PNG

Reduce PNG file size with smart color reduction, keeping transparency.

Files never leave your device
Instant, no queue
No upload, no signup
Free, no watermark

Drop your files here

or browse from your device

JPG, PNG, WebP, GIF, BMP, HEIC or AVIF images · up to 50 MB each · paste with ⌘V / Ctrl+V

Processed on your device, never uploaded

How it works

How to use compress png

Add PNG files such as screenshots, icons or logos.

Optionally limit the longest side if the images are larger than needed.

Click Compress PNG. Colors are reduced to an optimized palette where that is invisible, and transparency is preserved.

Questions

Frequently asked questions

PNG is lossless, so the tool reduces file size by quantizing the image to an optimized palette of up to 256 colors, the same technique used by popular PNG optimizers. For screenshots, icons and flat graphics the result looks identical; photos with smooth gradients may show slight banding.