🚀 Day 74/150 – Sort Dictionary by Keys in Python

Dictionaries are one of the most commonly used data structures in Python. Sometimes, you may want to display or process dictionary data in a sorted order based on its keys. Python provides several simple ways to achieve this.

Let's explore four different methods to sort a dictionary by its keys.

🔹 Method 1 – Using sorted()

The sorted() function returns the dictionary keys in alphabetical order.

student = {
    "name": "John",
    "age": 20,
    "course": "Python"
}

for key in sorted(student):
    print(key, ":", student[key])

Output

age : 20
course : Python
name : John

Explanation

• sorted(student) sorts all keys alphabetically.
• We then access each value using student[key].

🔹 Method 2 – Creating a Sorted Dictionary

You can create an entirely new dictionary with keys already sorted.

student = {
    "name": "John",
    "age": 20,
    "course": "Python"
}

sorted_dict = {key: student[key] for key in sorted(student)}

print(sorted_dict)

Output

{'age': 20, 'course': 'Python', 'name': 'John'}

Explanation

• Dictionary comprehension creates a new dictionary.
• Keys are inserted in sorted order.

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🔹 Method 3 – Using dict(sorted())

A concise and commonly used approach.

student = {
    "name": "John",
    "age": 20,
    "course": "Python"
}

sorted_dict = dict(sorted(student.items()))

print(sorted_dict)

Output

{'age': 20, 'course': 'Python', 'name': 'John'}

Explanation

• items() returns key-value pairs.
• sorted() sorts those pairs by key.
• dict() converts the sorted list back into a dictionary.

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🔹 Method 4 – Using Another Dictionary

Works for any dictionary data.

data = {
    "banana": 3,
    "apple": 5,
    "mango": 2
}

sorted_data = dict(sorted(data.items()))

print(sorted_data)

Output

{'apple': 5, 'banana': 3, 'mango': 2}

Explanation

• Keys are sorted alphabetically.
• Useful when working with real-world datasets.

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🎯 When to Use Which Method?

Method	Best Use Case
sorted()	Display keys in sorted order
Dictionary Comprehension	Create a new sorted dictionary
dict(sorted())	Clean and concise solution
User Dictionary Example	Practical real-world sorting

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💡 Pro Tip

To sort a dictionary in reverse alphabetical order, use:

sorted_dict = dict(sorted(data.items(), reverse=True))

Output

{'mango': 2, 'banana': 3, 'apple': 5}

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✅ Sorting dictionaries by keys is a useful skill when displaying reports, organizing data, or preparing outputs for users. Python's built-in sorted() function makes the task simple and efficient.