How to convert a string to a boolean in Python?

In this python tutorial, you will learn how to convert a string to a boolean.

Table Of Contents

In Python, True and False are the two boolean values. So we will see 4 ways to convert strings to boolean values.

Convert a string to a boolean using bool()

Here, we will directly use the bool() method to convert a string to a boolean value. If the string is empty, then the returned boolean value is False, otherwise, it is True.

Syntax:

bool(inp_str)

Parameter:

It takes inp_str as the only parameter, that refers to the actual input string.

Example 1

In this example, we will convert the string – “Welcome to thisPointer” to a boolean.

# Consider the string
inp_str= "Welcome to thisPointer"

print("Actual String: ",inp_str)

print(type(inp_str))

# Convert to boolean string
converted=bool(inp_str)

print("Boolean value: ",converted)
print(type(converted))

Output:

Actual String:  Welcome to thisPointer
<class 'str'>

Boolean value:  True
<class 'bool'>

The string is converted to boolean – True, since it is not empty and also we displayed the class i.e. bool.

Example 2

In this example, we will convert the string – “” (empty) to boolean.

inp_str= ""

print("Actual String: ",inp_str)
print(type(inp_str))

# Convert to boolean string
converted=bool(inp_str)

print("Boolean Value: ",converted)
print(type(converted))

Output:

Actual String:  
<class 'str'>
Boolean Value:  False
<class 'bool'>

A string is converted to boolean – False, since it is empty and also we displayed the class i.e. bool.

Convert a string to a boolean using strtobool()

The strtobool() function available in the distutils.util module, and it is used to convert the string values to 1 or 0. Value 1 represents True and 0 represents False.
Here,
1. It can take 3 types of string values for True i.e. Positive values – “Yes”, “True”, or “On”. For these values, strtobool() return 1.
2. It can take 3 types of string values for False i.e. Negative values – No, False, and Off. For these values, strtobool() return 0.

The strtobool() function can take only one of the above mentioned values.

Syntax:

distutils.util.strtobool("Yes/No/True/False/On/Off")

Parameter:

It takes one of the above possible values as a parameter.

Example 1
In this example we will convert the strings -Yes, True, and On to a boolean value.

# Import util module
import distutils
from  distutils import util

# Convert Yes to boolean
print(distutils.util.strtobool("Yes"))

# Convert True to boolean
print(distutils.util.strtobool("True"))

# Convert On to boolean
print(distutils.util.strtobool("On"))

Output:

1
1
1

Strings are converted to boolean – True.

Example 2

In this example, we will convert the strings -No, False and Off to boolean.

# Import util module
import distutils
from  distutils import util

# Convert No to boolean
print(distutils.util.strtobool("No"))

# Convert False to boolean
print(distutils.util.strtobool("False"))

# Convert Off to boolean
print(distutils.util.strtobool("Off"))

Output:

0
0
0

Strings are converted to boolean – False.

Convert a string to a boolean using json.loads()

The json.loads() function is available in the json module, and it is used to convert the string values (true/false) to boolean values (True/False).

1. json.loads() can convert – “true” to boolean True.
2. json.loads() can convert – “false” to boolean False.

Syntax:

json.loads("true".lower())

Parameter:

It takes a string value as a parameter

Example 1

In this example, we will convert the string “true” to boolean True.

# Import the json module
import json

# Convert true to boolean - True
value = json.loads("true".lower())

print(value)

Output:

True

The string is converted to boolean – True.

Example 2

In this example, we will convert the string “false” to boolean False.

import json

# Convert false to boolean - False
value = json.loads("false".lower())

print(value)

Output:

False

The string is converted to boolean – False.

Convert a string to a boolean using eval()

The eval() function is used to evaluate the expressions. It can be possible to convert the string to a boolean value using this.

1. eval(“True”) converts string “True” to True
2. eval(“False”) converts string “False” to False

Example 1

In this example, we will convert the string “True” to boolean True.

# Convert True to boolean True
print(eval("True"))

Output:

True

The string is converted to boolean – True.

Example 2

In this example, we will convert the string “False” to boolean False.

# Convert False to boolean False
print(eval("False"))

Output:

False

The string is converted to boolean – False.

Summary

In this tutorial, we have seen different ways to convert a string to a boolean value – True/False using bool(), json.loads(),eval() and strtobool(). we will directly use the bool() method to convert a string to a boolean value. If the string is empty, then the boolean value is False, Otherwise, it returns True. Whereas, strtobool() available in distutils.util module used to convert the string values to 1 or 0, here 1 represents True and 0 represents False. The json.loads() available in json module is used to convert the string values (true/false) to boolean values (True/False). The eval() method is used to evaluate the expression. It can be used to convert the string to a boolean value. Happy Learning.