How to fix IndexError: tuple index out of range

When you’re working with tuples in Python, you might see the following error:

IndexError: tuple index out of range

This error usually occurs when you try to access an index that doesn’t exist. It could be that you count the index wrong as a tuple index starts from zero.

Let’s see an example that causes this error and how to fix it.

How to reproduce this error

Suppose you have a tuple that contains the names of cities as follows:

cities = ("London", "Kuala Lumpur", "Wellington")

Now, suppose you want to print the name Wellington to the terminal with print(), so you access the tuple index as follows:

print(cities[3])

But instead of printing the city name, Python responds with this error:

Traceback (most recent call last):
  File "main.py", line 3, in <module>
    print(cities[3])
IndexError: tuple index out of range

You receive an error because index 3 doesn’t exist in the cities tuple.

A tuple index starts from 0, so the available index in cities are:

• 0 for London
• 1 for Kuala Lumpur
• 2 for Wellington

When you specify any other number as the index you want to access, you’ll get the tuple index out of range error.

How to fix this error

To resolve this error, make sure you’re accessing an index that exists in your tuple.

The correct index number to access Wellington is 2, so this is the correct code:

print(cities[2])  # Wellington

If you use a for loop and range to iterate over a tuple, make sure that the range numbers you specified are inside the range of available index numbers.

Failing to do so will trigger this error as well. Suppose you try to access the second and third items of the cities tuple like this:

cities = ("London", "Kuala Lumpur", "Wellington")

for i in range(1, 4):
    print(cities[i])

The range syntax above produce numbers 1, 2, and 3, so it’s the equivalent of this code:

print(cities[1])
print(cities[2])
print(cities[3])

Because cities index only goes up to 2, Python shows this error with the last print statement:

Kuala Lumpur
Wellington
Traceback (most recent call last):
  File "main.py", line 4, in <module>
    print(cities[i])
IndexError: tuple index out of range

To avoid this error, make sure you’re specifying a range that’s within the tuple index. Revise the code as follows:

cities = ("London", "Kuala Lumpur", "Wellington")

for i in range(1, 3):
    print(cities[i])

Now you won’t see the error in the output:

Kuala Lumpur
Wellington

The last two items are successfully printed. The code is free from error.

Conclusion

The IndexError: tuple index out of range occurs when you access a tuple using an index number that’s outside of the available range. To fix this error, make sure your tuple has an item at the index number you specified.

I hope this tutorial helps. See you again in other articles! 👍