This is hands down the best Pinyin Chart online and its FREE!
Yang Yang, the site’s owner provides videos within the chart to help you pronounce hard pinyin properly.
When appropriate, she shows you how your mouth should be shaped as the words are formed and where your tongue should be.
Click on “Video-based Pinyin Chart” in top menu to access this chart.
This entry contains an affiliate link, but as you will I am not motivated by that. It truly is the best out there.
Yang Yang was my first teacher, and I love her.