jQuery calculate sum of values in all text fields

If you don't need to support IE8 then you can use the native Javascript Array.prototype.reduce() method. You will need to convert your JQuery object into an array first:

 var sum = $('.price').toArray().reduce(function(sum,element) {
     if(isNaN(sum)) sum = 0;
     return sum + Number(element.value);
 }, 0);

Reference: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce

A tad more generic copy/paste function for your project.

sumjq = function(selector) {
    var sum = 0;
    $(selector).each(function() {
        sum += Number($(this).text());
    });
    return sum;
}

console.log(sumjq('.price'));

Similarly along the lines of these answers written as a plugin:

$.fn.sum = function () {
    var sum = 0;
    this.each(function () {
        sum += 1*($(this).val());
    });
    return sum;
};

For the record 1 * x is faster than Number(x) in Chrome

​

$('.price').blur(function () {
    var sum = 0;
    $('.price').each(function() {
        sum += Number($(this).val());
    });

    // here, you have your sum
});​​​​​​​​​