How to Count Vowels in a String Using Python

In Python, we can easily count how many vowels are in a string using a loop and counting the number of vowels we find in the string.

def countVowels(string):
    count = 0
    string = string.lower()
    for char in string:
        if char in "aeiou":
           count = count + 1
    return count

print(countVowels("Hello World!"))

#Output:
3

When working with strings, it can be useful to know how many vowels appear inside a variable.

In Python, we can easily get the count of vowels in a string looping over each character of the string and seeing if it is a vowel or not.

The vowels include “a”,”e”,”i”,”o”, and “u”.

Below is a function which will count the number of vowels for you in a string using Python.

def countVowels(string):
    count = 0
    string = string.lower()
    for char in string:
        if char in "aeiou":
           count = count + 1
    return count

print(countVowels("Hello World!"))
print(countVowels("This is a string with some words."))
print(countVowels("What's up?"))

#Output:
3
8
2

Counting the Number of Times Each Vowel Appears in a String Using Python

The example above is useful if you want to get the total number of vowels in a string. We can also use Python to get the count of how many times each vowel appears in a string.

To do this, we will loop over the vowels and create a dictionary which stores the count for each of the vowels.

Below is a function which will get the count of how many times each vowel appears in a given string.

def countEachVowel(string):
    counts = {}
    string = string.lower()
    for vowel in "aeiou":
        counts[vowel] = string.count(vowel)
    return counts

print(countEachVowel("Hello World!"))
print(countEachVowel("This is a string with some words."))
print(countEachVowel("What's up?"))

#Output:
{'a': 0, 'e': 1, 'i': 0, 'o': 2, 'u': 0}
{'a': 1, 'e': 1, 'i': 4, 'o': 2, 'u': 0}
{'a': 1, 'e': 0, 'i': 0, 'o': 0, 'u': 1}

Hopefully this article has been useful for you to count the number of vowels in a string using Python.