Python – Check If String Ends with a Number

In this tutorial, we will look at how to check if a string in Python ends with a number (digit) or not with the help of some examples.

How to check if a string ends with a numeric character?

To check if a string in Python ends with a number or not, check if the last character in the string is a digit or not using the string isdigit() function.

The built-in string isdigit() function in Python takes a string and returns True if all the characters in the string are numeric characters and there is at least one character in the string. It returns False otherwise.

So, use the string isdigit() function to check if the last character in the string (character at index -1) is a digit. The following is the syntax –

# check if string ends with a number
s[-1].isdigit()

It returns True if the string ends with a numeric character.

Examples

Let’s now look at some examples. First, we will create some strings that we will use throughout this tutorial.

# create strings
s1 = "cloud9"
s2 = "apple"
s3 = "rapper@"
s4 = ""

# display the strings
print(s1)
print(s2)
print(s3)
print(s4)

Output:

cloud9
apple
rapper@

Here, we created four strings – s1, s2, s3 and s4. The string s1 ends with a digit, the string s2 ends with an alphabet, the string s3 ends with the special character '@' and the string s4 is an empty string.

Let’s now check if the strings s1, s2, and s3 end with a digit or not.

# check if string ends wtih a number
print(s1[-1].isdigit())
print(s2[-1].isdigit())
print(s3[-1].isdigit())

Output:

True
False
False

We get True for s1 as it does end with a digit. We get False for s2 and s3 as they do not end with a digit.

Now let’s apply the above method to the empty string, s4.

# check if string ends wtih a number
print(s4[-1].isdigit())

Output:

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
Input In [4], in <module>
      1 # check if string ends wtih a number
----> 2 print(s4[-1].isdigit())

IndexError: string index out of range

We get an IndexError because we’re trying to access an index that does not exist (an empty string does not have a -1 index).

To avoid the above error, you can first check whether the string is non-empty and then proceed to check if the last character is a digit or not. See the example below –

# function to check if string ends wtih a digit
def check_str_ends_with_digit(s):
    if s and s[-1].isdigit():
        return True
    else:
        return False

# check if string ends wtih a number
print(check_str_ends_with_digit(s4))

Output:

False

We get False as the output for the empty string.

You might also be interested in –

• Python – Check If a Character Appears Twice in String
• Python – Check If String Contains Vowels
• Python – Check If String Contains Lowercase Letters
• Python – Check If String Contains Uppercase Letters
• Python String Uppercase – With Examples
• Python String Lowercase – With Examples
• Python – Capitalize First Letter of Each Word
• Python – Check If All Characters in String are Same