How to get an unique ID from every user visiting my web page without the need of login in?

I want to have a Web page and identify every visitor somehow. Maybe using their MAC address. Is it possible to get the MAC address of visitors in my web page? or is there any other way to get what I want?

I don't want to make a login form because I hate when web pages ask me to log or to create an account, It would be better if the page just identify the device used on each case.

Thank you.