Booleans

bool

see below for details on how bools are validated and what values are permitted

A standard bool field will raise a ValidationError if the value is not one of the following:

• A valid boolean (i.e. True or False),
• The integers 0 or 1,
• a str which when converted to lower case is one of '0', 'off', 'f', 'false', 'n', 'no', '1', 'on', 't', 'true', 'y', 'yes'
• a bytes which is valid per the previous rule when decoded to str

Note

If you want stricter boolean logic (e.g. a field which only permits True and False) you can use StrictBool.

Here is a script demonstrating some of these behaviors:

from pydantic import BaseModel, ValidationError


class BooleanModel(BaseModel):
    bool_value: bool


print(BooleanModel(bool_value=False))
#> bool_value=False
print(BooleanModel(bool_value='False'))
#> bool_value=False
print(BooleanModel(bool_value=1))
#> bool_value=True
try:
    BooleanModel(bool_value=[])
except ValidationError as e:
    print(str(e))
    """
    1 validation error for BooleanModel
    bool_value
      Input should be a valid boolean [type=bool_type, input_value=[], input_type=list]
    """