Unindent does not match any outer indentation level python ошибка

Python uses indentation to define the scope and extent of code blocks in constructs like class, function, conditional statements and loops. You can use both spaces and tabs to indent your code, and if you use both methods when writing your code, you will raise the error: IndentationError: unindent does not match any outer indentation level.

We will go through the error in detail and an example to learn how to solve it.

IndentationError: unindent does not match any outer indentation level

What is Indentation in Python?

Indentation is vital for constructing programs in Python. It refers to the correct use of white space to start a code block. With indentations, we can quickly identify the beginning and endpoint of any code block in our program. Let’s look at how indentation in Python works visually:

To indicate a code block in Python, you must indent each block line by the same amount. You can use four spaces or one tab, a typical indentation for Python. According to the conventions in PEP 8, four white spaces is preferable. You can use indentation to nest code blocks within code blocks.

Python objects if you use both spaces and tabs to indent your code. You need to use one form of indentation, and this can be tricky because you cannot see the difference between spaces and tabs.

The error commonly occurs when you copy code from other sources to your script. The code you are copying may have a different indentation to what you are using.

The error can also occur if you have used indentation in the wrong place or have not used any indentation.

Example: Mixing Indentation in Function

Let’s write a program that calculates the square roots of a list of numbers and prints the result to the console. We will start by defining the function to calculate the square root of a number:

def get_square_roots(number_list):

    for number in number_list:

        sqrt_number = number ** 0.5

	    print(f'The square root of {number} is {sqrt_number}')

The function uses a for loop to iterate through every number in the list you will pass. We use the exponentiation operator to calculate the square root of the number and then print the result. Next, we will define the list of numbers and then call the get_square_roots() function.

number_list = [4, 9, 16, 25, 36]

get_square_roots(number_list)

Let’s run the code and see what happens:

sqrt_number = number ** 0.5
                          ^
IndentationError: unindent does not match any outer indentation level

The code returns the IndentationError, and the tick indicates the line responsible for the error.

Solution

We can use a text editor like Sublime Text to see the indentation style in our code by highlighting it, as shown below.

Each line represents a tab, and a dot represents a space. We can see a mix of spaces and tabs in the code snippet, particularly the line sqrt_number = number ** 0.5. To fix this, you can change replace the indentation on the other lines with four white spaces as this is the preferred indentation method. Alternatively, you can use tabs. Let’s look at the revised code in the text editor:

We can see each line has spaces instead of tabs. Let’s run the code to see what happens:

The square root of 4 is 2.0
The square root of 9 is 3.0
The square root of 16 is 4.0
The square root of 25 is 5.0
The square root of 36 is 6.0

The program returns the square root of each number in the list we pass to the function. You do not need to use a text editor to find differences in indentation style, but it does make it easier to spot them. Alternatively, you can manually go through each line in your code and stick to one indentation style.

Summary

Congratulations on reading to the end of this tutorial! The error “indentationerror: unindent does not match any outer indentation level” occurs when you mix spaces and tabs to indent your code. To solve this error, ensure all your code uses either spaces or tabs in your program. You can use a text editor to highlight your code to make it easier to spot the differences. Otherwise, you can go over the lines in your code and stick to one indentation style. To minimise the likelihood of this error, you can write your code in a text editor or Integrated Development Environment (IDE) like PyCharm, which automatically indent your code in a consistent style.

For further reading on Python code structure, go to the article: How to Solve Python UnboundLocalError: local variable referenced before assignment.

Go to the online courses page on Python to learn more about Python for data science and machine learning.

Have fun and happy researching!

In this tutorial, you’ll learn how to fix a common error you’ll encounter in Python, the indentation error. Indenting your code is an important function for writing useful programs. However, indenting code improperly will raise the following error: “Python indentationerror: unindent does not match any outer indentation level”.

By the end of this tutorial, you’ll have learned:

• How to fix the Python indentation error
• How indentation works in Python and why it matters
• How to use popular IDEs, such as VS Code, to easily resolve the Python indentation error

Let’s get started!

What is the Python Indentation Error?

The Python indentationerror is caused by a number of different factors:

• Mixing spaces and tabs in indentation
• Mismatched levels of indentation in code blocks

Both of these scenarios will cause the indentationerror to be raised. Unfortunately, it’s not immediately clear which of these scenarios caused the error to happen. Before we dive into further details, let’s explore how indentation works in Python.

How Indentation Works in Python

Python allows you to indent your code with either spaces or tabs. It doesn’t matter which one you choose – however it requires you to be consistent in that choice. Because Python is a statically typed language, Python will not be able to work properly if spaces and tabs are both used for indentation.

In fact, when copying code from the internet, this is a common error you’ll encounter. Throughout the rest of this tutorial, you’ll learn how to identify and resolve this error.

Should You Indent with Spaces or Tabs in Python?

While it doesn’t matter whether you use tabs or spaces to indent your code, Python does provide some guidance as to which methods are preferred. The PEP-8 standard on indenting your code indicates that using four spaces per indentation level is the preferred method of indenting your code.

The PEP standard goes even further. It says that spaces are preferred and that tabs should only be used to remain consistent with existing code.

Causes of the Python Indentation Error

Let’s explore the causes of the Python indentationerror a little further. Earlier, you learned that the error is caused by mixing spaces and tabs in indenting code as well as having improperly indented code.

Let’s explore both of these in further detail in order to see how the error can be resolved.

Mixing Spaces and Tabs in Python

One of the most common causes of the Python indentationerror is mixing tabs and spaces in your code when indenting. The problem with this is that it’s often not intuitive to find. This problem mostly occurs when you copy and paste code from another source into a Python program.

Thankfully, most modern IDEs will account for this and automatically convert tabs into spaces. For example, Visual Studio Code will, by default, convert tabs into the corresponding number of spaces. Because of this, this error is more common when you’re running Python programs in other applications.

In many cases, you’ll be able to select tabs using find and replace by searching for the t string.

Incorrect Indenting in Python

The other cause of the Python indentationerror is having incorrect indenting in your Python code. This can occur when you’re writing any blocked type pieces of code, such as if-else statements or for loops.

Let’s take a look at an example that would throw a Python indetationerror:

# This code will throw a Python indentation error
for i in range(10):
print(i)

You can fix this easily by indenting the second like of code, as shown below:

# Fixing a Python indentationerror
for i in range(10):
    print(i)

Being mindful of where your code needs to be indented is an important step in writing error-free code. Generally, following a colon, your code will need to be indented.

Conclusion

In this tutorial, you learned how to solve the Python indentationerror. You learned what causes the Python indentationerror and how to solve its two main causes. First, we looked at how the error is thrown when your code mixes both spaces and tabs. Then, we looked at missing or erroneous indentations of your code.

Additional Resources

To learn more about related topics, check out the tutorials below:

• Python IndexError: List Index Out of Range Error Explained
• Python For Loop Tutorial – All You Need to Know!
• Introduction to Python Programming (Beginner’s Guide)

Sign Up for Our Newsletters

Subscribe to get notified of the latest articles. We will never spam you. Be a part of our ever-growing community.

By checking this box, you confirm that you have read and are agreeing to our terms of use regarding the storage of the data submitted through this form.

Indenting your code can be a messy business if you try to use both spaces and tabs. In Python, using both methods of indentation results in an error. This error is “indentationerror: unindent does not match any outer indentation level”.

In this guide, we talk about what this error means and when it is raised. We walk through an example of this error in action to help you learn how to fix it.

indentationerror: unindent does not match any outer indentation level

Python code can be indented with tabs or spaces. It’s up to you.

Python only has an objection when you use both spaces and tabs to indent your code. Python requires you use only one method of indentation. This is because the language is statically typed. Statically typed programming languages are sticklers when it comes to syntax. 

Indentation errors are a difficult one to understand because it involves the invisible: mixing spaces and tabs. Depending on the code editor you are using, you may not even be able to see whether spaces or tabs have been used until you delete your indents from your code.

IndentationErrors are common when you copy code snippets from the internet. Every developer has their own preference when it comes to indentation and you’ll often find code snippets do not adhere to your own preferences. Some snippets will indent with spaces.

If a code snippet you copy into your program uses a different type of indentation, you may see an IndentationError in your code. This is because you mix tabs and spaces.

An Example Scenario

Write a program that finds the factors of a number.

Start by defining a function to calculate the factors of a number:

def get_factors(number):
	for i in range(1, number + 1):
		if number % i == 0:
			print("{} is a factor of {}.".format(i, number))

This function uses a for loop to iterate through every number in the range of 1 and the number we have specified plus 1.

In each iteration, our program checks if there is a remainder after dividing “number” by “i”. We do this using the modulo operator. If there is not a remainder, “i” is a factor of “number”.

If a number is a factor of “number”, a message is printed to the console.

We to call our function:

This code calculates all the factors of 32. Run our code and see what happens:

  File "test.py", line 4
	print("{} is a factor of {}.".format(i, number))
                                               	^
IndentationError: unindent does not match any outer indentation level

Our code returns an IndentationError.

The Solution

We have made a mistake with the styling of our code. We know this because IndentationErrors are raised when there is a problem with how your code is indented.

Take a look at how our code is styled. In Sublime Text, we can see the styles of our code by hovering over each line:

Each line represents a tab. Each dot represents a space. You can see that we have mixed up both spaces and tabs in our code snippet. Python likes consistency in indents and so the interpreter returns an error when we run our code.

If you use a text editor that does not support this behavior, check whether your code uses spaces or tabs by backspacing your indentation. If your code removes a tab when you press the backspace key, that part of your code is using tabs.

Spaces are the preferred method of indentation in Python but you can use tabs if you want.

Let’s revise our code:

def get_factors(number):
		for i in range(1, number + 1):
				if number % i == 0:
						print("{} is a factor of {}.".format(i, number))

We have replaced all the spaces with tabs. Run our program again:

1 is a factor of 32.
2 is a factor of 32.
4 is a factor of 32.
8 is a factor of 32.
16 is a factor of 32.
32 is a factor of 32.

Our code successfully returns a list of all the factors of 32. This shows us that our code was logically accurate all along. It was our indentation that caused the problem.

Conclusion

The “indentationerror: unindent does not match any outer indentation level” error is raised when you use both spaces and tabs to indent your code.

To solve this error, check to make sure that all your code uses either spaces or tabs in a program. Now you’re ready to resolve this common Python error like a professional software developer!