Get a Value from a Dictionary by Key in Python

This article explains how to get a value from a dictionary (dict) by key in Python.

If you want to find keys based on their values, refer to the following article.

• Get keys from a dictionary by value in Python

You can retrieve all the values from a dictionary as a list by applying the list() function to its values() method.

• Iterate through dictionary keys and values in Python

d = {'key1': 1, 'key2': 2, 'key3': 3}

print(list(d.values()))
# [1, 2, 3]

Get a value from a dictionary with dict[key] (KeyError for non-existent keys)

In Python, you can get a value from a dictionary by specifying the key like dict[key].

d = {'key1': 'val1', 'key2': 'val2', 'key3': 'val3'}

print(d['key1'])
# val1

In this case, KeyError is raised if the key does not exist.

# print(d['key4'])
# KeyError: 'key4'

Using a non-existent key is acceptable when adding a new element to the dictionary.

d['key4'] = 'val4'
print(d)
# {'key1': 'val1', 'key2': 'val2', 'key3': 'val3', 'key4': 'val4'}

For more information about adding items to the dictionary, see the following article.

• Add and update an item in a dictionary in Python

Use the in keyword to check whether a key exists in the dictionary.

• Check if a key/value exists in a dictionary in Python

Use dict.get() to get the default value for non-existent keys

You can use the get() method of a dictionary (dict) to get a value without an error. If the key does not exist, a default value can be returned.

• Built-in Types - dict.get() — Python 3.13.3 documentation

Specify the key as the first argument. If the key exists, the corresponding value is returned. Otherwise, None is returned.

d = {'key1': 'val1', 'key2': 'val2', 'key3': 'val3'}

print(d.get('key1'))
# val1

print(d.get('key4'))
# None

You can provide a default value as the second argument, which will be returned if the key is not found.

print(d.get('key4', 'NO KEY'))
# NO KEY

print(d.get('key4', 100))
# 100

The original dictionary remains unchanged.

print(d)
# {'key1': 'val1', 'key2': 'val2', 'key3': 'val3'}