Font Size Calculator

font_size_calculator.js

const base = 19;
const ratio = 1.618;
const interval = 5;

function size(point) {
  const s = base * Math.pow(ratio, point/interval);
  return [s, `${(s / base).toFixed(3)} rem`];
}

for (let i = -10; i < 20; i++) {
  console.log(size(i));
}