how to count letters in string using js code example

Example 1: how get count of letters in javascript

//when use length for string this will be return the count of charactor 
//in string
$("#about_me_textarea").val().length

Example 2: how to count specific letters in string js

console.log(("str1,str2,str3,str4".match(/,/g) || []).length); //logs 3

console.log(("str1,str2,str3,str4".match(new RegExp("str", "g")) || []).length); //logs 4