How do I round a number in JavaScript?

javascript floating-point numbers rounding
Ace picture Ace · Oct 29, 2008 · Viewed 92.7k times · Source

While working on a project, I came across a JS-script created by a former employee that basically creates a report in the form of

Name : Value
Name2 : Value2

etc.

The peoblem is that the values can sometimes be floats (with different precision), integers, or even in the form 2.20011E+17. What I want to output are pure integers. I don't know a lot of JavaScript, though. How would I go about writing a method that takes these sometimes-floats and makes them integers?

Answer

Raj Rao picture Raj Rao · Jan 25, 2009

If you need to round to a certain number of digits use the following function

function roundNumber(number, digits) {
            var multiple = Math.pow(10, digits);
            var rndedNum = Math.round(number * multiple) / multiple;
            return rndedNum;
        }

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