Which values are always considered False?

Certain values like 0 and empty strings ("") are automatically considered False in conditional statements.

These values can be used to control program flow—for example, when the result of an arithmetic operation is 0.

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a = 2
b = 3

if a - b:
    print("a - b is not 0.")
else:
    print("a - b is 0.")

• Numeric 0 (integer 0, float 0.0)

• Empty string ""

• Empty list [], empty tuple (), empty dictionary {}

• None

When these values are passed to an if statement, the condition is evaluated as False and the block of code does not execute.

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if 0:
    print("This will not execute.")
else:
    print("0 is evaluated as False.")


if "":
    print("This will not execute.")
else:
    print("An empty string is evaluated as False.")