Check If a Value is a Number Not a String in Python

John on October 26, 2021

To check a value is a number data type in Python and not a string, we can use the Python type() function with some logic.

The three main number data types to evaluate are int float and decimal:

import decimal

print(type(decimal.Decimal(4)))
print(type(int(4)))
print(type(float(4)))

<class 'decimal.Decimal'>
<class 'int'>
<class 'float'>

Now we can create some logic to check if the value is equal to the type, decimal.Decimal, int or float like this:

num = '4'

if type(num) == decimal.Decimal or type(num) == int or type(num) == float:
   print('It is a number.')
else:
   print('Is a string some other data type.')

Is a string some other data type.