How to parse float with two decimal places in javascript?

Performance considerations

Performance is key, and every millisecond counts. Keep the performance car running by using Math.round() technique to maintain the number type and avoid the string conversion that toFixed() brings.

let number = Math.round(parseFloat('123.456') * 100) / 100; // 123.46, and performance remains unharmed! 🎯
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Handling different precision values

When the requirement is to handle numbers of different decimal precision, it's handy to have a custom method like the following:

Number.prototype.round = function(precision) {
  let factor = Math.pow(10, precision);
  return Math.round(this * factor) / factor;
};

let roundAndProud = parseFloat('123.456').round(2); // 123.46. Now, that's precision! 🎩🔍
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In-depth application scenarios

Handling floating-point arithmetic issues

With floating-point numbers, be mindful of precision challenges, sometimes, toFixed() might act like a mischievous imp!

(0.1 + 0.2).toFixed(2); // "0.30", can be misleading, right?
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Avoid precision pitfalls by doing the calculations first, rounding comes later.

Formatting currency amounts

Precision is Mr.Important when dealing with money matters. Intl.NumberFormat is our currency hero:

let formatter = new Intl.NumberFormat('en-US', {
  style: 'currency',
  currency: 'USD',
  minimumFractionDigits: 2,
});

let moneyTalks = formatter.format(123456.789); // "$123,456.79", hey big spender! 💵
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Parsing special numbers with care

Handle different inputs like integers and strings elegantly. You wouldn't want unnecessary decimals for integer inputs:

parseFloat('100').toFixed(2); // "100.00", a bit overzealous, don't you think?
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In case you are dealing with strings that look like a currency notation, ensure to parse the number correctly:

parseFloat('$123,456.78'.replace(/[^\d.-]/g, '')).toFixed(2); // "123456.78" - no more dollar signs, clean as a whistle!
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