Page keyword density query code implemented with js_javascript skills

I have been looking for a keyword density query tool on the Internet for a long time, but I still haven’t found a suitable keyword density query tool. Why? Because my site is encoded in utf-8, and most of the information available online is GB2312. I continued to look for keyword density query tools and found one, but instead of entering the URL, I had to copy the code myself. Although this kind of keyword density query tool is not very convenient to use, I have not found a better keyword density query tool for a while. If you find one, be sure to contact me. Requirement: As long as the keyword density query tool you are looking for supports UTF-8 encoding.