Math - Round to Decimal

round-to-decimal.js

/**
 * This gist is for Javascript beginners.
 * @author: Anthony Du Pont <[email protected]>
 * @site: https://www.twitter.com/JsGists
 * @source: Coding Math/Keith Peters
 *
 * You often get floating numbers in Javascript and sometimes you need to round them and
 * keep only n decimals. They are many solutions to do so but let me show you my favorite.
 *
 * Example:
 * I have a floating number and I want it to be rounded at the 3rd decimal.
 **/

const num = roundToDecimal(1.0457784523, 3); // Return 1.046

// Number: The number we want to round.
// Places: The number of decimals we want to keep.
function roundToDecimal(number, places) {
  const multiplier = Math.pow(10, places); // For our example the multiplier will be 10 * 10 * 10 = 1000.
  return Math.round(number * multiplier) / multiplier;
}