How to print all the keys of a dictionary in Python

A Python dictionary is an unordered collection of data values that stores key-value pairs. In this article, we will explore various methods to print all the keys of a dictionary in Python.

Using dict.keys() Method

The dict.keys() method returns a dictionary view object containing all the keys. This is the most direct way to access all keys in a dictionary ?

Example

dictionary = {
    'Novel': 'Pride and Prejudice',
    'year': '1813',
    'author': 'Jane Austen',
    'character': 'Elizabeth Bennet'
}

print(dictionary.keys())

The output of the above code is ?

dict_keys(['Novel', 'year', 'author', 'character'])

Using dictionary.items() Method

The items() method returns key-value pairs. We can iterate through these pairs and print only the keys ?

Example

dictionary = {
    'Novel': 'Pride and Prejudice',
    'year': '1813',
    'author': 'Jane Austen',
    'character': 'Elizabeth Bennet'
}

for key, value in dictionary.items():
    print(key)

The output of the above code is ?

Novel
year
author
character

Converting Keys to List

You can convert the dictionary keys to a list using the list() function. This creates a permanent list of all keys ?

Example

dictionary = {
    'Novel': 'Pride and Prejudice',
    'year': '1813',
    'author': 'Jane Austen',
    'character': 'Elizabeth Bennet'
}

# Converting keys to a list
keys_list = list(dictionary.keys())
print(keys_list)

The output of the above code is ?

['Novel', 'year', 'author', 'character']

Using List Comprehension

List comprehension provides a concise way to iterate through dictionary keys and print each one individually ?

Example

my_dict = {'name': 'Alice', 'age': 30, 'city': 'New York'}

# Using list comprehension to print each key
[print(key) for key in my_dict]

The output of the above code is ?

name
age
city

Using itemgetter from operator Module

The itemgetter() function from the operator module can extract the first element (key) from each key-value pair ?

Example

from operator import itemgetter

def get_keys(dictionary):
    return list(map(itemgetter(0), dictionary.items()))

dictionary = {
    'Novel': 'Pride and Prejudice',
    'year': '1813',
    'author': 'Jane Austen',
    'character': 'Elizabeth Bennet'
}

print(get_keys(dictionary))

The output of the above code is ?

['Novel', 'year', 'author', 'character']

Comparison

Conclusion

The dict.keys() method is the most straightforward approach for accessing dictionary keys. Use list(dict.keys()) when you need the keys as a list, and choose iteration methods when processing keys individually.