I've been racking my head as to trying to understand why when using Number.prototype.toLocaleString, it is multiplying my number by 100.

var num = 5;
alert(num + ' vs ' + num.toLocaleString('en-GB', { style: 'percent' }));

I've been racking my head as to trying to understand why when using Number.prototype.toLocaleString, it is multiplying my number by 100.

var num = 5;
alert(num + ' vs ' + num.toLocaleString('en-GB', { style: 'percent' }));

Reading through all the reference guides, I have not seen anything that suggests it should be.

Have I pletely missed the point?

• javascript

3 Answers 3

From the spec:

If the value of numberFormat.[[style]] is "percent", let x be 100 × x.

it expects a number in the range of [0, 1] which then would be formated to something between 0% and 100%

It's percent not toLocaleString that is causing this, and the reason is that the percentage is measured by numbers from 0 to 1 as 0% to 100%, so if you want 5%, use :

var num = .05;
alert(num + ' vs ' + num.toLocaleString('en-GB', { style: 'percent' }));

More @ Number.prototype.toLocaleString()

As many other systems do, toLocaleString's percent style interprets 1 as 100 %.

This is a mon way of expressing percentages (such as in probability theory where a 100 % probability is 1).