Table of Contents
1. Use len() to count the total length of the list
2. Use count() to count the number of occurrences of a specific element
3. Statistics the number of occurrences of all elements (using collections.Counter )
4. Use dictionary to manually count (without Counter)
summary
Home Backend Development Python Tutorial python count items in list example

python count items in list example

Jul 24, 2025 am 02:58 AM
java programming

Use len() to count the total number of elements in the list, such as len([1, 2, 3, 4, 5]) to return 5; 2. Use count() to count the number of occurrences of a specific element, such as ['apple', 'banana', 'apple'].count('apple') to return 3; 3. Use collections.Counter to count the frequency of each element, such as Counter(['a', 'b', 'a']) to output Counter({'a': 3, 'b': 2, 'c': 1}); 4. Use dictionary to manually count the traversal and get methods to achieve the same effect, such as loop accumulation to obtain {'a': 3, 'b': 2, 'c': 1}.

python count items in list example

There are many ways to count the number of elements in a list in Python. Here are some common examples and usage scenarios.

python count items in list example

1. Use len() to count the total length of the list

If you want to count the total number of elements in the list (regardless of duplication or not):

 my_list = [1, 2, 3, 4, 5]
count = len(my_list)
print(count) # Output: 5

2. Use count() to count the number of occurrences of a specific element

If you want to count how many times an element appears in the list:

python count items in list example
 my_list = ['apple', 'banana', 'apple', 'cherry', 'apple']
count_apple = my_list.count('apple')
print(count_apple) # Output: 3

Note: count() is case sensitive and only counts exactly matched items.

 ['Apple', 'apple'].count('apple') # Output: 1

3. Statistics the number of occurrences of all elements (using collections.Counter )

If you want to know how many times each element in the list appears, it is recommended to use Counter :

python count items in list example
 from collections import Counter

my_list = ['a', 'b', 'a', 'c', 'b', 'a']
counter = Counter(my_list)
print(counter) # Output: Counter({'a': 3, 'b': 2, 'c': 1})

# Get the count of an element print(counter['a']) # Output: 3

# Get the most common element print(counter.most_common(1)) # Output: [('a', 3)]

4. Use dictionary to manually count (without Counter)

You can also use normal dictionaries to implement similar functions:

 my_list = ['a', 'b', 'a', 'c', 'b', 'a']
count_dict = {}

for item in my_list:
    count_dict[item] = count_dict.get(item, 0) 1

print(count_dict) # Output: {'a': 3, 'b': 2, 'c': 1}

summary

  • Total number: use len(list)
  • The number of times a certain element is to be used: use list.count(item)
  • To the frequency of all elements: use collections.Counter(list)

Basically, these commonly used methods are not complicated but very practical.

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