I’ve been working with JavaScript for over a decade, and one of the simplest ways to handle precise rounding is using toFixed(). So if you’re looking to javascript round to two decimal places, here’s a reliable method I often use:
var discount = (100 - (price / listprice) * 100).toFixed(2);
This gives you a string value with exactly two decimal places. If you’re using it in further calculations, you’ll want it as a number:
var discount = parseFloat((100 - (price / listprice) * 100).toFixed(2));
Clean and effective for formatting values like percentages or prices.