Number 2 Words

number-2-words.js

function number2words(n) {
  // works for numbers between 0 and 999999
  console.log('input:', n);
  const map = {
    'singleUnits': ['zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine'],
    'doubleUnits': ['eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen'],
    'tenths': ['ten', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety']
  };
  let output;
  const t = Math.floor(n / 1000); // thousands
  const h = Math.floor((n - t * 1000) / 100); // hundreds
  const u = n - t * 1000 - h * 100; // units
  console.log('thousands:', t);
  console.log('hundreds:', h);
  console.log('units:', u);

  function getUnits(num) {
    let output = (num < 10) ? map.singleUnits[num] : (num % 10 === 0) ? map.tenths[num / 10 - 1] : (num < 20) ? map.doubleUnits[num % 10 - 1] : null;
    if (output === null) {
      const tenths = Math.floor(num / 10);
      const units = num % 10;
      output = map.tenths[tenths - 1] + '-' + map.singleUnits[units];
    }
    return output;
  }
  const unitsStr = getUnits(u);
  console.log('unitsStr:', unitsStr);

  const hundredsStr = (h) ? map.singleUnits[h] + ' hundred ' : null;
  console.log('hundredsStr:', hundredsStr);

  let thousandsStr = (t > 0 && t < 10) ? map.singleUnits[t] + ' thousand ' : null;
  if (thousandsStr === null) {
    const hundreds = Math.floor(t / 100);
    const tenths = Math.floor((t - hundreds * 100) / 10);
    const units = t - hundreds * 100 - tenths * 10;
    console.log('thousands decomp:', hundreds, tenths, units);
    thousandsStr = '';
    if (hundreds) { thousandsStr += map.singleUnits[hundreds] + ' hundred '; }
    if (tenths && units) { thousandsStr += (tenths < 2) ? map.doubleUnits[units - 1] + ' thousand ' : map.tenths[tenths - 1] + '-' + map.singleUnits[units] + ' thousand '; }
    else if (tenths && !units) { thousandsStr += map.tenths[tenths - 1] + ' thousand '; }
    else if (!tenths && units) { thousandsStr += map.singleUnits[units] + ' thousand '; }
    else if (!tenths && !units && thousandsStr) { thousandsStr += 'thousand '; }
  }
  console.log('thousandsStr:', thousandsStr);

  output = unitsStr;
  console.log('output, unitsStr:', unitsStr);
  if (hundredsStr && hundredsStr !== 'zero') { output = (output !== 'zero') ? hundredsStr + output : hundredsStr; }
  if (thousandsStr && thousandsStr !== 'zero') { output = (output !== 'zero') ? thousandsStr + output : thousandsStr; }
  return output.trim();
}

// TEST
number2words(0); // "zero"
number2words(10); // "ten"
number2words(19); // "nineteen"
number2words(22); // "twenty-two"
number2words(80); // "eighty"
number2words(100); // "one hundred"
number2words(301); // "three hundred one"
number2words(99999); // "ninety-nine thousand nine hundred ninety-nine"
number2words(888888); // "eight hundred eighty-eight thousand eight hundred eighty-eight"

Number2Words.markdown

Number 2 Words

Function number2words(n) returns number represented as a string of words.

Example: number2words(888888) returns "eight hundred eighty-eight thousand eight hundred eighty-eight"

Scripts by V.

License.