how to convert binary string to decimal?

I want to convert binary string in to digit E.g

var binary = "1101000" // code for 104
var digit = binary.toString(10); // Convert String or Digit (But it does not work !)
console.log(digit);

How is it possible? Thanks

The parseInt function converts strings to numbers, and it takes a second argument specifying the base in which the string representation is:

var digit = parseInt(binary, 2);

See it in action.

Use the radix parameter of parseInt:

var binary = "1101000";
var digit = parseInt(binary, 2);
console.log(digit);

parseInt() with radix is a best solution (as was told by many):

But if you want to implement it without parseInt, here is an implementation:

  function bin2dec(num){
    return num.split('').reverse().reduce(function(x, y, i){
      return (y === '1') ? x + Math.pow(2, i) : x;
    }, 0);
  }