There are a lot of free and online softwares for optimizing PNG images, here is a short list of them:
- PunyPNG (talked about in this blog post) :
The default is 150 KB and 15 files, but if you donate you get the increase of 500 KB and uploads up to 75 files 🙂
PunyPNG, for me is one of the most efficient PNG compressors out there, first of all it’s online, so you can access it anywhere, and second, it’s really is pretty good at compressing compared to other compressors out there.
See comparison chart on their website: http://punypng.com/about/comparison
PunyPNG website: http://punypng.com/
- Smush.it™
Smush.it is by Yahoo! and it is also available online.
From the website:
Smush.it uses optimization techniques specific to image format to remove unnecessary bytes from image files. It is a “lossless” tool, which means it optimizes the images without changing their look or visual quality. After Smush.it runs on a web page it reports how many bytes would be saved by optimizing the page’s images and provides a downloadable zip file with the minimized image files.
Smush.it website: http://www.smushit.com/ysmush.it/
- ImageOptim
ImageOptim is free and open source! And its for Mac users.
From the website:
ImageOptim optimizes images — so they take up less disk space and load faster — by finding best compression parameters and by removing unnecessary comments and color profiles. It handles PNG, JPEG and GIF animations.
ImageOptim website: http://imageoptim.pornel.net/
- PNGShrink PNG file compressor for Mac
Website: http://www.macupdate.com/app/mac/33222/pngshrink
- Ping! PNG file compressor for Mac
Website: http://www.macupdate.com/app/mac/23055/ping!
Other sources:
- 10 Free Tools to Optimize and Compress PNG Images
- 4 Free Tools to Optimize and Compress PNG Images Without Losing Quality
I don’t really know which one is the best, so what I do is I drop everything in ImageOptim first and then, I upload those that are less than 500KB to PunyPNG to see if it can compress a bit more. And then dump those that are more than 500KB to Smush.it, Smush.it doesn’t have a file size limit you see (at least it doesn’t say it does, but it couldn’t upload my 2MB PNG file). And until all those tell me that are are no more savings, that prolly means that I have compressed my PNGs until they can no longer be compressed.
Michelle Chen 