Python String isalnum() Method

One minute read
python string methods

By Lenin Mishra

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Python String isalnum() method

The isalnum() method in Python checks if all characters in the string are alphanumeric.

Alphanumeric characters - Alphabet letters (a-z) and numbers (0-9)

Syntax of isalnum() method
string.isalnum()

Returns True or False
Example 1

Code

s1 = "Pylenin1992"

print(s1.isalnum())

Output

True
Example 2 - Check for a sentence

Code

s1 = "Pylenin was born in 1992"

print(s1.isalnum())

Output

False
Example 3 - Check for special characters

Code

s1 = "pylenin1992@gmail.com"

print(s1.isalnum())

Output

False

As you can see, @ is not an alphanumeric character.

Let’s check for random characters.

Code

s1 = "!#%&?"

print(s1.isalnum())

Output

False

Check out other commonly used Python string methods.

  1. How to create a string in Python?
  2. How to access characters in a Python string?
  3. How to replace characters in a string in Python?
  4. How to concatenate strings in Python?
  5. How to iterate through a string in Python?
  6. Check if a Substring is Present in a Given String in Python
  7. Escape sequences in Python String
  8. Python String Formatting - The Definitive Guide