JavaScript: Count the number of vowels in a given string

JavaScript validation with regular expression: Exercise-8 with Solution

Count Vowels

Write a JavaScript function to count the number of vowels in a given string.

Test Data:
console.log(alphabetize_string('United States'));
Output :
"SUadeeinsttt"

Pictorial Presentation:

Sample Solution:

JavaScript Code:

function vowel_count(str) {

  return str.match(/[aeiou]/gi).length;

}

console.log(vowel_count('The quick brown fox jumps over the lazy dog'));

Output:

11

Flowchart:

Live Demo:

See the Pen javascript-regexp-exercise-8 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that counts the vowels in a string using a loop and a set of vowel characters.
• Write a JavaScript function that uses a regular expression to match all vowels and returns their count.
• Write a JavaScript function that counts vowels case-insensitively in a given string and handles empty strings.
• Write a JavaScript function that removes non-alphabetic characters before counting vowels to ensure accuracy.

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