compresspng Compress a PNG

Lossless PNG Compression

Strip the waste, keep every single pixel. The safe option when the image must not change at all.

Lossless only

Drag & drop files here, or

Accepts .png

  1. Upload your PNG files.
  2. Each is re-packed with no pixel changes.
  3. Download identical images in smaller files.

This mode does not touch your pixels. It re-encodes the PNG with maximum compression effort and strips redundant chunks, so the image that comes out is bit-for-bit identical when decoded — the file around it is just packed better.

Savings are real but modest: commonly 5–15%, occasionally more on files exported by software that optimises poorly. If a file is already tightly packed there may be nothing left to remove, in which case you get your original back unchanged rather than a slightly larger re-encode.

Guides about Lossless PNG optimiser

Quality and transparency How to Compress a PNG Without Losing Quality Lossless compression caps at 15%. Real savings come from palette reduction, which is invisible on most images. 7 min read

More compresspng.net tools

Compress PNG Shrink PNG files by 60–80% while keeping transparency and crisp edges. Free, no watermark, no signup. Compress PNG to a target size Need it under 100 KB? Pick the ceiling and the compressor works down to it automatically. PNG to JPG For photographs, changing format beats any amount of PNG compression — often by 10×. Resize PNG Cap the longest edge at 1920px. The fastest way to cut size when the image is simply bigger than it needs to be.

Frequently asked questions

Is this really lossless?
Yes. Decode the input and the output and you get identical pixel data, including the alpha channel. Only encoding overhead is removed.
Why did my file barely shrink?
Because it was already well compressed. Lossless optimisation can only remove waste, and some exporters leave very little. For a bigger reduction try the palette-based strengths on the main compressor.
Why did I get back a file the same size as the original?
If re-encoding would have produced a larger file, the original is returned instead. A compressor should never hand you something bigger than what you uploaded.