Javascript toFixed Not Rounding

Question

I'm using javascript to bind to some checkboxes, and the toFixed(2) is not rounding up. Any ideas why it's not rounding? For instance, if the number is 859.385 it's only displaying 859.38 instead of 859.39.

I've also read that the toFixed can round differently depending on which browser you are using, anyone know of a way around this so that my javascript calculations match my php calculations?

var standardprice = parseFloat($('#hsprice_'+this.id.split('_')[1]).val()); var price =  parseFloat($('#hprice_'+this.id.split('_')[1]).val()); var discount =  parseFloat($('#hdiscount_'+this.id.split('_')[1]).val()); var deposit =  parseFloat($('#hdeposit_'+this.id.split('_')[1]).val());  var currSprice = parseFloat($('#hTotalSprice').val()); var currPrice = parseFloat($('#hTotalPrice').val()); var currDiscount = parseFloat($('#hTotalDiscount').val()); var currDeposit = parseFloat($('#hTotalDeposit').val());  currSprice += standardprice; currPrice += price; currDiscount += discount; currDeposit += deposit;  $('#lblTotalSprice').text('$'+addCommas(currSprice.toFixed(2))); $('#lblTotalPrice').text('$'+addCommas(currPrice.toFixed(2))); $('#lblTotalDiscount').text('$'+addCommas(currDiscount.toFixed(2))); $('#lblTotalDeposit').text('$'+addCommas(currDeposit.toFixed(2)));  $('#hTotalSprice').val(currSprice.toFixed(2)); $('#hTotalPrice').val(currPrice.toFixed(2)); $('#hTotalDiscount').val(currDiscount.toFixed(2)); $('#hTotalDeposit').val(currDeposit.toFixed(2)); 

Answer 1

I have yet to find a number that toFixed10 does wrong. Can anybody else?

Thanks to blg and his answer which pointed me to Mozilla's toFixed10() method.

Using that I came up with this short one liner, which indeed covers all cases mentioned here...

function toFixed( num, precision ) {     return (+(Math.round(+(num + 'e' + precision)) + 'e' + -precision)).toFixed(precision); } 

Answer 2

I made this to use in all financial data as a best rounding function. You can test it on all problematic numbers. Javascript allows some sort of precision, so I used it to make almost every number be rounded as expected.

function roundTo(n, digits) {         if (digits === undefined) {             digits = 0;         }          var multiplicator = Math.pow(10, digits);         n = parseFloat((n * multiplicator).toFixed(11));         return Math.round(n) / multiplicator;     }