Capitalize the first letter of every word in a string

Use String.prototype.replace() to match the first character of each word and String.prototype.toUpperCase() to capitalize it.

const capitalizeEveryWord = str =>
  str.replace(/\b[a-z]/g, char => char.toUpperCase());

// EXAMPLE
capitalizeEveryWord('hello world!'); // 'Hello World!'

Source

https://www.30secondsofcode.org/js/s/capitalize-every-word