KeyError: popitem(): dictionary is empty (Fix)

Fix the Python error "KeyError: popitem(): dictionary is empty". This error happens when you call popitem() on a dictionary that has no items left.

This page explains what the error means, shows a small example that causes it, and gives simple ways to avoid it.

Quick fix

Check that the dictionary is not empty before calling popitem():

data = {}

if data:
    key, value = data.popitem()
else:
    print("Dictionary is empty")

An empty dictionary is False, so if data: is a simple way to avoid this error.

What this error means

popitem() is a dictionary method that removes and returns one key-value pair.

If the dictionary is empty, there is nothing to remove. Python raises:

KeyError: 'popitem(): dictionary is empty'

If you are new to dictionaries, see Python dictionaries explained.

Example that causes the error

This code creates an empty dictionary and then calls popitem() on it:

data = {}
data.popitem()

Output:

Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
KeyError: 'popitem(): dictionary is empty'

Why this fails:

data is {}, which means it has no key-value pairs
popitem() tries to remove one pair
There is nothing to remove, so Python raises KeyError

If you want to learn more about how this method works, see the Python dictionary popitem() method.

Why it happens

This error usually happens for one of these reasons:

The dictionary started empty
Items were removed earlier in the program
A loop kept calling popitem() after the dictionary became empty
You expected data from another function, but it returned an empty dictionary

Here is a common loop mistake:

data = {"a": 1}

while True:
    print(data.popitem())

This removes the only item first. On the next loop, the dictionary is empty, so the error happens.

How to fix it

There are a few simple ways to fix this error.

Check if the dictionary has items

This is the clearest fix for beginners:

data = {"name": "Alice"}

if data:
    item = data.popitem()
    print(item)
else:
    print("Dictionary is empty")

Output:

('name', 'Alice')

if data: works because:

non-empty dictionaries are True
empty dictionaries are False

Use an explicit length check

If you want to be more explicit, use len():

data = {}

if len(data) > 0:
    print(data.popitem())
else:
    print("Dictionary is empty")

This does the same thing, but if data: is shorter and more common.

Use try-except when empty dictionaries are expected

Sometimes an empty dictionary is normal in your program. In that case, you can catch the error:

data = {}

try:
    key, value = data.popitem()
    print(key, value)
except KeyError:
    print("Dictionary is empty")

This works, but for beginners, an if check is usually easier to read.

Review earlier code

Sometimes popitem() is not the real problem. The real issue is that the dictionary became empty earlier.

For example:

data = {"x": 1, "y": 2}

data.clear()
data.popitem()

data.clear() removes everything, so popitem() fails after that.

If you are removing a specific key instead of an arbitrary item, see how to remove a key from a dictionary in Python.

Recommended beginner-safe pattern

The safest pattern is:

Check whether the dictionary is empty
Use popitem() only when there is at least one item
Handle the empty case with a message, return value, or different logic

Example:

def remove_one_item(data):
    if data:
        return data.popitem()
    return None

info = {}
result = remove_one_item(info)

print(result)

Output:

None

This is usually clearer than relying on exceptions for normal program flow.

Debugging steps

If you are not sure why the error is happening, inspect the dictionary right before popitem().

Useful checks:

print(my_dict)
print(len(my_dict))
print(bool(my_dict))
print(my_dict.keys())

What these show:

print(my_dict) shows the full dictionary
print(len(my_dict)) shows how many items it has
print(bool(my_dict)) shows False when it is empty
print(my_dict.keys()) shows the current keys

You can also:

Print the dictionary right before popitem()
Trace where items are removed earlier
Check whether clear(), pop(), or another popitem() emptied it
If using a loop, make sure the loop stops when the dictionary becomes empty

A safe loop looks like this:

data = {"a": 1, "b": 2}

while data:
    print(data.popitem())

print("Done")

Output:

('b', 2)
('a', 1)
Done

Common mistakes

These are common causes of this error:

Calling popitem() on {}
Using popitem() inside a while loop without checking if items remain
Removing all dictionary items earlier with clear(), pop(), or popitem()
Assuming loaded or returned data is non-empty when it is actually empty

If you are dealing with a broader dictionary key problem, see KeyError in Python: causes and fixes.

If your code depends on checking for a key before removing or reading it, see how to check if a key exists in a dictionary in Python.

FAQ

What does `popitem()` return?

It returns one key-value pair as a tuple, like ('name', 'Alice').

Why is this a `KeyError`?

Because popitem() tries to remove a dictionary key, but there is no key to remove.

How do I check if a dictionary is empty?

Use if my_dict:. An empty dictionary is False.

Should I use try-except or an if check?

For beginners, an if check is usually simpler and easier to read.