How to get a list of all keys from a python dictionary?
Jun 28, 2025 am 12:33 AMThe most straightforward way to get a list of all keys in a Python dictionary is to use the .keys() method of the dictionary and convert it to a list. 1. Use the dict.keys() method to return the view object and convert it into a list through list(), such as list(my_dict.keys()); 2. Collect keys when traversing the dictionary, such as [k for k in d] or list(d), the effect is equivalent to .keys(); 3. Use the unpacking operator, such as [d], which is suitable for Python 3.5, with a short writing method but poor readability. These methods are basically consistent in function, and the choice depends on the code style and specific needs.
The most straightforward way to get a list of all keys in a Python dictionary is to use the .keys()
method of the dictionary and convert it into a list. For example:

my_dict = {'a': 1, 'b': 2, 'c': 3} keys_list = list(my_dict.keys())
This gives you a list of all keys.

Use dict.keys()
to get the key list
This is the most common and recommended method. dict.keys()
returns a view object that dynamically reflects the changes in the dictionary. If you just want to get all the keys at once, just use list(my_dict.keys())
.
- If you are using Python 3,
.keys()
returns a view, not a list, so you must uselist()
to turn it. - In Python 2,
.keys()
returns directly to the list without conversion.
example:

d = {'name': 'Alice', 'age': 30} print(list(d.keys())) # Output: ['name', 'age']
You can also get all keys through the dictionary
If you collect keys while traversing the dictionary, you can also achieve the goal:
d = {'x': 10, 'y': 20} keys_list = [k for k in d]
This method is essentially the same as list(d)
, because the traversal dictionary is to traverse its keys by default.
- This writing method is concise, but its readability is slightly worse than
list(d.keys())
- More suitable for nesting in other expressions, such as list comprehension
Using *
unpacking operator (Python 3.5)
If you like a more "blazing" way of writing, you can use the unpacking operator:
d = {'a': 1, 'b': 2} keys_list = [*d]
This method uses Python's unpacking mechanism to expand all keys of the dictionary and recombine them into a list.
- Short writing style, suitable for those familiar with this technique
- Beginners may not be easy to understand
- Performance is similar to the previous ones
Basically these are the methods. Although there are not many ways, each has its own applicable scenario: if you want clarity, use .keys()
. If you need simplicity, you can consider unpacking or traversing directly. It depends on your code style and requirements.
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