When I first started working with Python dictionaries, I often needed to create a copy but exclude one or two keys.
At first, I thought Python would have a built-in method for this. However, just as in Excel, where you sometimes need a workaround, in Python, you also need to employ different techniques.
Over the years, I’ve tried many approaches. Some are quick and simple, while others give you more control.
In this tutorial, I’ll show you four practical methods to copy a Python dictionary without one key. I’ll explain each method with examples, so you can choose the one that best suits your project.
Method 1 – Use Dictionary Comprehension
The most efficient way to copy a dictionary without one key is to use a Python dictionary comprehension. This method is fast, clean, and easy to read.
Here’s how I usually do it:
# Original dictionary
employee = {
"name": "John Doe",
"age": 35,
"city": "New York",
"salary": 85000
}
# Copy dictionary without the 'salary' key
new_employee = {k: v for k, v in employee.items() if k != "salary"}
print("Original Dictionary:", employee)
print("New Dictionary:", new_employee)Output:
Original Dictionary: {'name': 'John Doe', 'age': 35, 'city': 'New York', 'salary': 85000}
New Dictionary: {'name': 'John Doe', 'age': 35, 'city': 'New York'}I executed the above example code and added the screenshot below.
Here, the comprehension loops through all key-value pairs and excludes the one with the “salary” key.
I like this method because it’s concise and doesn’t modify the original dictionary. It’s also very flexible; you can exclude multiple keys by adding them to a set.
Method 2 – Use dict.copy() and pop()
Sometimes, I prefer using Python’s built-in copy() method along with pop(). This approach makes sense if you want to start with a full copy and then remove one key.
# Original dictionary
employee = {
"name": "Jane Smith",
"age": 42,
"city": "Chicago",
"department": "Finance"
}
# Copy dictionary
new_employee = employee.copy()
# Remove one key
new_employee.pop("department", None)
print("Original Dictionary:", employee)
print("New Dictionary:", new_employee)Output:
Original Dictionary: {'name': 'Jane Smith', 'age': 42, 'city': 'Chicago', 'department': 'Finance'}
New Dictionary: {'name': 'Jane Smith', 'age': 42, 'city': 'Chicago'}I executed the above example code and added the screenshot below.
Here, .pop(“department”, None) removes the key safely. If the key doesn’t exist, it won’t throw an error.
I use this method when I want to be explicit about which key I’m removing. It’s also easy to extend if you want to remove multiple keys one by one.
Method 3 – Use del on a Copy
Another easy option is to copy a Python dictionary and then use del to delete a key. This is similar to pop(), but it doesn’t return the value.
# Original dictionary
employee = {
"name": "Michael Johnson",
"age": 29,
"city": "Los Angeles",
"role": "Software Engineer"
}
# Copy dictionary
new_employee = employee.copy()
# Delete key
if "role" in new_employee:
del new_employee["role"]
print("Original Dictionary:", employee)
print("New Dictionary:", new_employee)Output:
Original Dictionary: {'name': 'Michael Johnson', 'age': 29, 'city': 'Los Angeles', 'role': 'Software Engineer'}
New Dictionary: {'name': 'Michael Johnson', 'age': 29, 'city': 'Los Angeles'}I executed the above example code and added the screenshot below.
I find this method useful when I’m sure the key exists. It’s also very readable for beginners who are just getting started with Python.
Method 4 – Use a Helper Function
When I need to reuse this logic across multiple parts of a project, I like to write a small helper function. This makes the code cleaner and avoids repeating myself.
def copy_without_key(d, key):
"""Return a copy of dictionary d without the specified key."""
return {k: v for k, v in d.items() if k != key}
# Example usage
employee = {
"name": "Emily Davis",
"age": 31,
"city": "Houston",
"bonus": 5000
}
new_employee = copy_without_key(employee, "bonus")
print("Original Dictionary:", employee)
print("New Dictionary:", new_employee)Output:
Original Dictionary: {'name': 'Emily Davis', 'age': 31, 'city': 'Houston', 'bonus': 5000}
New Dictionary: {'name': 'Emily Davis', 'age': 31, 'city': 'Houston'}I recommend this method if you’ll be excluding keys often. It keeps your code DRY (Don’t Repeat Yourself) and makes it easy to maintain.
Which Method Should You Use?
- If you want a one-liner → use dictionary comprehension.
- If you want explicit removal → use copy() + pop().
- If you’re sure the key exists → use del on a copy.
- If you need reusability → write a helper function.
Copying a Python dictionary without one key is a common task, especially when working with large datasets or cleaning up JSON responses from APIs.
I’ve shown you four methods that I personally use in real-world projects. Each has its strengths, and the one you choose depends on your coding style and needs.
Next time you’re working with dictionaries, try out these methods and see which one feels most natural to you.
You may also read other Dictionary tutorials:
- Convert Dict to String in Python
- Get All Values From a Dictionary in Python
- Python Get First Key in Dictionary
- Python Dictionary contains
I am Bijay Kumar, a Microsoft MVP in SharePoint. Apart from SharePoint, I started working on Python, Machine learning, and artificial intelligence for the last 5 years. During this time I got expertise in various Python libraries also like Tkinter, Pandas, NumPy, Turtle, Django, Matplotlib, Tensorflow, Scipy, Scikit-Learn, etc… for various clients in the United States, Canada, the United Kingdom, Australia, New Zealand, etc. Check out my profile.
