PunyPNG, developed by Gracepoint After Five, is a free image optimization tool that dramatically reduces page load times by reducing the file size of an image without any loss of quality. PunyPNG uses several web optimization techniques to compress PNG, JPEG, and GIF images for reducing the image file sizes. It analyzes the content of your image and figures out the best image format to use. Depending on the file, PunyPNG will automatically convert your GIF into a PNG format and then further compress that. For JPEGs, sometimes it’s better to make it a PNG, and other times it’s better to keep it as JPEG and use jpeg-tran to optimize it. PunyPNG supports the most popular image formats and is constantly improving its arsenal of optimization techniques such as dirty transparency and animated PNG support.

• http://www.gracepointafterfive.com/punypng/