How to Check if a Number is Odd Or Even in Python in 3 ways

In this post, you can find 3 different ways to check if a number is odd or even in Python.

Lets see few examples of checking if number is even or odd in Python:

Modulus Operator (%)

number = 5

if number % 2 == 0:
    print(f"{number} is even")
else:
    print(f"{number} is odd")

result:

5 is odd

Note: be careful with floating points. Understanding of odd/even for floating points might differ. Example:

number = 5.54

if number % 2 == 0:
    print(f"{number} is even")
else:
    print(f"{number} is odd")

result:

5.54 is odd

We can use simple trick to detect odd and even numbers in Python

number = 7

if number & 1:
    print(f"{number} is odd")
else:
    print(f"{number} is even")

result:

7 is odd

How it works

check whether the last bit of the number
- if last bit is set then the number is odd
- otherwise even

Example of numbers in binary notation :

To check multiple numbers if they are odd or even in Python we can use list comprehension:

[("even" if x % 2 == 0 else "odd") for x in range(5)]

We will check first five numbers and the result is:

['even', 'odd', 'even', 'odd', 'even']

Finally to check Pandas column for odd or even numbers we can create function and apply it on the column by:

def is_odd(num):
        return num & 1 and True or False

df_t['numbers'].apply(is_odd, axis=1)