Count Vowels

BeginnerStrings

Task

Implement `countVowels(str)` counting occurrences of a, e, i, o, u — **case-insensitive**. 'y' doesn't count.

0 / 2

⚠️ Reveal official solutions

Try solving it yourself first — struggling is where the learning happens.

Recommended — explicit character handling with no edge cases.

function countVowels(str) {
  let count = 0;
  for (const ch of str.toLowerCase()) {
    if ('aeiou'.includes(ch)) count++;
  }
  return count;
}

Concise, but remember match() returns null when nothing matches.

function countVowels(str) {
  const matches = str.match(/[aeiou]/gi);
  return matches ? matches.length : 0;
}