Removing commas is potentially dangerous because, as others have mentioned in the comments, many locales use a comma to mean something different (like a decimal place).

I don't know where you got your string from, but in some places in the world "2,299.00" = 2.299

The Intl object could have been a nice way to tackle this problem, but somehow they managed to ship the spec with only a Intl.NumberFormat.format() API and no parse counterpart :(

The only way to parse a string with cultural numeric characters in it to a machine recognisable number in any i18n sane way is to use a library that leverages CLDR data to cover off all possible ways of formatting number strings http://cldr.unicode.org/

The two best JS options I've come across for this so far:

• https://github.com/google/closure-library/tree/master/closure/goog/i18n
• https://github.com/globalizejs/globalize

One way is to remove all the commas with:

strnum = strnum.replace(/\,/g, '');

and then pass that to parseInt:

var num = parseInt(strnum.replace(/\,/g, ''), 10);

But you need to be careful here. The use of commas as thousands separators is a cultural thing. In some areas, the number 1,234,567.89 would be written 1.234.567,89.

Here it is annotated

originalNum = '1,022.55';
cleanNum = originalNum.replace(",", "");
float = parseFloat(cleanNum);
console.log(float);

Alternatively you can just make it a one-liner by using

float = parseFloat('1,022.55'.replace(",", ""));
console.log(float);