How to Sort Dictionary by Key in Python: Simple Guide

To sort a dictionary by key in Python, use the sorted() function on the dictionary's keys and create a new dictionary from the sorted keys. This can be done simply with sorted_dict = {k: original_dict[k] for k in sorted(original_dict)}.

Syntax

Use the sorted() function on the dictionary keys to get them in order. Then, create a new dictionary by looping over these sorted keys.

• sorted(dict): Returns a list of keys sorted in ascending order.
• {k: dict[k] for k in sorted(dict)}: Dictionary comprehension to build a new dictionary with keys in sorted order.

python

sorted_dict = {k: original_dict[k] for k in sorted(original_dict)}

Example

This example shows how to sort a dictionary by its keys and print the sorted dictionary.

python

original_dict = {'banana': 3, 'apple': 4, 'pear': 1, 'orange': 2}
sorted_dict = {k: original_dict[k] for k in sorted(original_dict)}
print(sorted_dict)

Output

{'apple': 4, 'banana': 3, 'orange': 2, 'pear': 1}

Common Pitfalls

One common mistake is trying to sort the dictionary directly, which does not work because dictionaries are unordered collections (before Python 3.7) or maintain insertion order (Python 3.7+), but do not sort themselves.

Another mistake is using dict.sort(), which is invalid because dictionaries do not have a sort() method.

Always use sorted() on keys or items and build a new dictionary.

python

wrong = {'banana': 3, 'apple': 4}
# wrong.sort()  # This will cause an AttributeError

# Correct way:
sorted_dict = {k: wrong[k] for k in sorted(wrong)}
print(sorted_dict)

Output

{'apple': 4, 'banana': 3}

Quick Reference

• sorted(dict): Returns sorted keys list.
• {k: dict[k] for k in sorted(dict)}: Creates sorted dictionary by keys.
• Dictionaries keep insertion order (Python 3.7+), so new dict is sorted.

Key Takeaways

Use sorted() on dictionary keys to get them in order.

Create a new dictionary with sorted keys using dictionary comprehension.

Dictionaries do not have a sort() method; sorting must be done externally.

From Python 3.7+, dictionaries keep insertion order, so new dict preserves sorted order.

Always build a new dictionary to get a sorted version by keys.