Python Type Casting

Type casting in Python is when you manually change the data type of a value using built-in functions. This is different from automatic type conversion—you decide what the type should be.

Converting Strings to Numbers

Let’s say you’re working with numbers stored as strings. Python won’t treat them like real numbers unless you cast them.

				
					data1 = "15"
data2 = "2.718"
data3 = "100"

converted_int = int(data1)       # From string to integer
converted_float = float(data2)   # From string to float
also_float = float(data3)        # Even though it's an int-like string, we cast to float

print(converted_int)     # Output: 15
print(converted_float)   # Output: 2.718
print(also_float)        # Output: 100.0

Converting Numbers to Strings

This is useful when displaying numbers in messages or combining them with other text.

				
					age = 25
temperature = 36.6

as_string1 = str(age)            # From integer to string
as_string2 = str(temperature)    # From float to string

print(as_string1)     # Output: "25"
print(as_string2)     # Output: "36.6"

Summary

Here’s a quick guide to Python’s basic casting functions:

int() → Converts string or float to integer (if possible)
float() → Converts string or int to float
str() → Converts int or float to string

Important Note: You can only cast strings to numbers if the string is a valid number. Otherwise, Python will throw an error.

				
					int("hello")  # ❌ This will raise ValueError

With type casting, you can make your code more flexible and interactive—especially when dealing with user input, file data, or web forms.

Keep practicing, and you’ll see how powerful and handy this concept is in real-world projects!