Python Boolean
Summary: in this tutorial, you’ll learn about the Python boolean data type, falsy and truthy values.
Introduction to Python Boolean data type
In programming, you often want to check if a condition is true or not and perform some actions based on the result.
To represent true and false, Python provides you with the boolean data type. The boolean value has a technical name as bool
.
The boolean data type has two values: True
and False
.
Note that the boolean values True
and False
start with the capital letters (T
) and (F
).
The following example defines two boolean variables:
is_active = True
is_admin = False
Code language: Python (python)
When you compare two numbers, Python returns the result as a boolean value. For example:
20 > 10
True
20 < 10
False
Code language: Python (python)
Also, comparing two strings results in a boolean value:
'a' < 'b'
True
'a' > 'b'
False
Code language: Python (python)
The bool() function
To find out if a value is True
or False
, you use the bool()
function. For example:
'Hi')
True
bool('')
False
bool(100)
True
bool(0)
False
bool(Code language: Python (python)
As you can see clearly from the output, some values evaluate to True
and the others evaluate to False
.
Falsy and Truthy values
When a value evaluates to True
, it’s truthy. And if a value evaluates to False
, it’s falsy.
The following are falsy values in Python:
- The number zero (
0
) - An empty string
''
False
None
- An empty list
[]
- An empty tuple
()
- An empty dictionary
{}
The truthy values are the other values that aren’t falsy.
Note that you’ll learn more about the None
, list
, tuple
, and dictionary
in the upcoming tutorials.
Summary
- Python boolean data type has two values:
True
andFalse
. - Use the
bool()
function to test if a value isTrue
orFalse
. - The falsy values evaluate to
False
while the truthy values evaluate toTrue
. - Falsy values are the number zero, an empty string, False, None, an empty list, an empty tuple, and an empty dictionary. Truthy values are the values that are not falsy.