This java script webapp analyzes your WhatsApp Chat history locally on your machine. Visit https://chatanalyzer.moritzwolf.com for the website which runs this code.
Please open an issue if the tool does not work. Please supply your data format (e.g. [07.09.17, 6:44:16 PM] NAME: message)
No chat data is getting uploaded anywhere. If you don't trust me turn off your internet connection after the site has loaded. :)