How to convert a currency string to a double with jQuery or Javascript?

Remove all non dot / digits:

var currency = "-$4,400.50";
var number = Number(currency.replace(/[^0-9.-]+/g,""));

accounting.js is the way to go. I used it at a project and had very good experience using it.

accounting.formatMoney(4999.99, "€", 2, ".", ","); // €4.999,99
accounting.unformat("€ 1.000.000,00", ","); // 1000000

You can find it at GitHub

Use a regex to remove the formating (dollar and comma), and use parseFloat to convert the string to a floating point number.`

var currency = "$1,100.00";
currency.replace(/[$,]+/g,"");
var result = parseFloat(currency) + .05;