How to Find the Index of the Max Value in a List in Python

The maximum value in a list is the element with the highest value. You can find the maximum value index in a list by passing the list to the built-in max() function and then using list.index(element) where the element is the max value. The list.index() method will return the index of the first occurrence of the maximum value.

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Example: List of Numbers

Let’s look at an example of finding the index of the max value in a list of numbers.

# Define list

my_list = [2, 5, 10, 99, 4]

# Get max value of the list

max_val = max(my_list)

# Get index of max value

max_idx = my_list.index(max_val)

# Print result

print(f'Max value in {my_list} is {max_val}, with the index {max_idx}')

Let’s run the code to get the result:

Max value in [2, 5, 10, 99, 4] is 99, with the index 3

Note that the index of a list starts from 0.

Example: List of Characters

We can also use the max value for characters, for example,

# Define string

my_str = 'fortyfive'

# Convert string to list of characters

my_list = list(my_str)

# Get maximum ASCII value

max_val = max(my_list)

# Get the index for the maximum value

max_idx = my_list.index(max_val)

# Print the result

print(f'Max value in {my_list} is {max_val}, with the index {max_idx}')

In the case of characters, the max() function will find the character with the maximum ASCII value. Let’s run the code to get the result:

Max value in ['f', 'o', 'r', 't', 'y', 'f', 'i', 'v', 'e'] is y, with the index 4

Summary

Congratulations on reading to the end of this tutorial!

For further reading on getting the index of a value from a list, go to the article:

How to Find the Index of the Min Value in a List in Python

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