Python all() Usage and Examples

Python built-in functions

The all() method will return True when all elements in the given iterable are true. If not, it will return False.

The syntax of the all() method is:

all(iterable)

all() parameter

The all() method takes one parameter:

• iterable - Any iterable containing elements (List,Tuple,Dictionaryetc.)

all() return value

The all() method returns:

• True-If all elements of iterable are true

• False-If any element of iterable is false

Example1How to use all() with lists?

# All values are true
l = [1,　3,　4,　5]
print(all(l))
# All values are false
l = [0, False]
print(all(l))
# A false value
l = [1,　3,　4, 0]
print(all(l))
# A value is true
l = [0, False,　5]
print(all(l))
# Empty iterable
l = []
print(all(l))

The output when running the program is:

True
False
False
False
True

any() method is used in a similar way for tuples and similar listsSet.

Example2How to use all() with strings?

s = 'This is good'
print(all(s))
# 0 is False
# '0' is True
s = '000'
print(all(s))
s = ''
print(all(s))

The output when running the program is:

True
True
True

Example3How to use all() with Python dictionaries?

For dictionaries, if all keys (non-values) are true or the dictionary is empty, all() returns True. Otherwise, it returns false for all other cases.

s = {0: 'False',　1: 'False'}
print(all(s))
s = {1: 'True',　2: 'True'}
print(all(s))
s = {1: 'True', False: 0}
print(all(s))
s = {}
print(all(s))
# 0 is False
# '0' is True
s = {'0': 'True'}
print(all(s))

The output when running the program is:

False
True
False
True
True

Python built-in functions