About this challenge
Count Vowels is a easy string manipulation coding challenge. It tests string-manipulation techniques: parsing, transforming, and searching text efficiently. Write your solution in the editor above, run it against the test cases, and get instant feedback — free, in your browser, no sign-up.
Show a hint & approach (spoiler)
Hint: Loop through the characters (lowercased) and check membership in the set {a,e,i,o,u}.
Keep practicing
Browse all coding challenges, or build intuition for the underlying concepts with the algorithm visualizers and the developer cheatsheets.