Python upper(), lower(), isupper(), and islower() Methods example

Sometimes we may need to Convert String characters to uppercase and lowercase, for this purpose Python provides us two methods:

• The upper() string method converts all of the characters to uppercase
• The lower() string method converts all of the characters to lowercase

upper() string method example

code

code = 'Codesource.io'
code.upper()
print(f'After converting to uppercase =\'{code.upper()}\'')

output

After converting to uppercase ='CODESOURCE.IO'

lower() string method example

code

code = 'Codesource.io'
code.lower()
print(f'After converting to lowercase =\'{code.lower()}\'')

output

After converting to lowercase ='code-source.tempurl.host'

isupper(), and islower() Methods

• The isupper() method will return a Boolean True value if the string has one or more letters & all the letters are uppercase
• The islower() method will return a Boolean True value if the string has one or letters & all the letters are lowercase

isupper() method example

code

code = 'CODESOURCE.IO'
code.isupper()
print(f'if string has all the uppercase letters =\'{code.isupper()}\'')

output

if string has all the uppercase letters ='True'

islower() method example

code

code = 'Codesource.io'
code.islower()
print(f'if string has all the lowercase letters =\'{code.islower()}\'')

output

if string has all the lowercase letters ='False'