Rounding a number to exactly two decimal places for currency formatting

Question

I need to round to two decimal places for currency.

Both

Math.round(num*Math.pow(10,2))/Math.pow(10,2)

and

Math.round(num*Math.pow(10,2))/Math.pow(10,2)

work except it cuts any trailing zero's off so I get 29.9 instead of 29.90.

What is the best way around this?

Answer 1

I am using this, seems to be ok

Math.round(x * 100)/100

Its look like shortest

Answer 2

You can add this to number which you want to set specific format

.toFixed(2)

Answer 3

(Math.round(num*Math.pow(10,2))/Math.pow(10,2)).toFixed(2)

Answer 4

It makes sense to think about it as a total amount of cents. 19.999 = 1999.9 cents, the 3rd decimal does not matter you cant pay it anyway.

This makes sense:

function convertToMoney(val){
    return (Math.floor(val*100).toFixed(0)/100).toFixed(2);
}