# Sum the second element of each tuple in a list in Python Last updated: Jun 29, 2022 Photo from Unsplash

## Sum the second element of each tuple in a list in Python#

Use a generator expression to sum the second element of each tuple in a list, e.g. `result = sum(tup for tup in list_of_tuples)`. The `sum()` function gets passed a generator object with the second element of each tuple in the list and returns the total.

main.py
```Copied!```list_of_tuples = [(10, 20), (30, 40), (50, 60)]

result = sum(tup for tup in list_of_tuples)

print(result)  # 👉️ 120
``````

The first step is to use a generator expression to iterate over the list of tuples.

Generator expressions are used to perform some operation for every element or select a subset of elements that meet a condition.

On each iteration, we access the tuple element at index `1` (the second tuple item) and return the result.

The example passes a generator object that contains the numbers `20`, `40`, `60` to the `sum()` function, which then returns `120`.

You can use this approach to sum the Nth element of each tuple in a list.

Here is an example that sums the first element of each tuple in a list.

main.py
```Copied!```list_of_tuples = [(10, 20), (30, 40), (50, 60)]

result = sum(tup for tup in list_of_tuples)

print(result)  # 👉️ 90
``````
Python indexes are zero-based. The first item in a tuple (or any other iterable) has an index of `0`, the second an index of `1`, etc.

An alternative approach is to unpack the second item from each tuple in the generator expression.

main.py
```Copied!```list_of_tuples = [(10, 20), (30, 40), (50, 60)]

result = sum(second for _, second in list_of_tuples)

print(result)  # 👉️ 120
``````

We only assigned the second item in the tuples to a variable.

The first item is stored in an underscore because it's not needed.

We basically unpack the second item from the tuple of the current iteration and assign the value to a variable.

main.py
```Copied!```first, second = (10, 20)

print(first)  # 👉️ 10
print(second)  # 👉️ 20
``````

When using this approach, you have to make sure to declare exactly as many variables as you have items in the tuple.

Which approach you pick is a matter of personal preference. I'd use directly index access as if I find it easier to read and more explicit.

I wrote a book in which I share everything I know about how to become a better, more efficient programmer. You can use the search field on my Home Page to filter through all of my articles.