This tool can give you a rough idea. Just respond whether you know each character or not.
The more responses you provide, the more accurate the estimate will be (you must provide at least 40).
Your definition of whether you know a charactar can be whatever you want.
If you only answer yes when you have completely mastered a character, then we will estimate how many you have completely mastered. If you are interested in how many characters you can recognize, then answer yes when you recognize it.