A better PNG minifer

6 years ago from , Programmer

Hi, my name is Ivan and I made an open-source PNG minification library several months ago: UPNG.js.

I want to make it available to more people, so I made a minification webapp UPNG. It has two main advantages over TinyPNG:

  • you can achieve a better compression thanks to the Quality parameter
  • it runs completely in a browser (no upload, download, no size limits)

You can drag-and-drop your files and keep the Quality parameter at default, or you can play with it to find the best balance between the size and the quality (thanks to the live preview of the result image).

I want it to be comfortable to use and pleasant to look at. I am just a programmer, so I will be very thankful for your comments and suggestions :)


  • Thom StoodleyThom Stoodley, 6 years ago

    what's with the rabbit?

    6 points
  • Oleg SerediucOleg Serediuc, 6 years ago

    Nice tool, although I have couple suggestions about the UI:

    • I uploaded 2000px x 1000px PNG, after transformation my image got cut inside the box and I couldn't see all parts of the file, scroll inside the box is disabled

    • 50/50 UI I for transformation area seems a bit too much, I would try 30/70 so there's more space for images

    • There's no clue indicating that images are being uploaded, so maybe some loader would be nice

    • There's no clear option to remove uploaded images

    • "Size" – • – "Quality" slider is too slow, maybe replace it with buttons, slider creates an expectation of instant result as you drag, which is not the case

    3 points
    • Ivan Kutskir, 6 years ago

      Thank you rof your comment!

      • I fixed it, now you can "navigate" the image with a mouse
      • The preview is just to see the quality, it is usually enough to see a small part.
      • The time that you waited was not uploading, but minification of PNG. Large PNGs can take 1 second to minify, or even more.
      • You can always remove images from a downloaded ZIP, or you can press F5 to start over. I don't want to add too many buttons, to make UI even more complex.
      • Slider is slow, because your large PNG was hard to minify. When you minify small images (e.g. 256x256 px icons), slider is much smoother.
      0 points
  • Jose PinoJose Pino, 6 years ago


    0 points
  • Ruslan Ianberdin, 6 years ago

    Wow, great tool. Thank you Ivan, I will use it instead tinypng ;)

    0 points
  • Hendrik Runte, 6 years ago

    The SSL cert of your site is dead.

    0 points