Web sites depend on a lot of images, and with higher resolution displays, their size will only increase. Yet website performance is critical as well; you want a great looking image in as small a file size as possible.
That’s where TinyPNG comes in handy. Cut your png of choice and use the site’s drag and drop uploader. TinyPNG will strip colors and compress pngs down to 8 bits while still retaining 100% transparency. I’ve used it on a few recent projects, and every thing I send to it reduces the file size by at least 50% with no noticeable image degradation.