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# Convert String to Int Python

In Python an strings can be converted into an integer using the Python built-in function. However, it’s important to note that the string must represent a valid integer value for the conversion to succeed.

Example

```Input: str_num = "1001"
Output: 1001
Explanation: In this, we are converting string into integer```

## Python Convert String to Int

In Python, you can convert a string into an integer using different functions in Python. This function takes a string as its argument and returns the corresponding integer value.

• Using int() function
• Using eval() function
• Using ast.literal_eval
• Using str.isdigit() function

## Convert a string to a number Method

### String to Int converter using int() function in Python

Here we will use int() function which will return the int data type.

## Python3

 `num ``=` `'10'`` ` `# check and print type num variable``print``(``type``(num))`` ` `# convert the num from string into int``converted_num ``=` `int``(num)`` ` `# print type of converted_num``print``(``type``(converted_num))`` ` `# We can check by doing some mathematical operations``print``(converted_num ``+` `20``)`

Output

```<class 'str'>
<class 'int'>
30

```

As a side note, to convert to float, we can use float() in Python

### String to Int Converter Using Eval() Function

Here we will use eval() methods to Convert String to Int

## Python3

 `# converting python string to``# int using eval() function``a ``=` `"100"``print``(``eval``(a)``+``12``)`

Output

```112

```

### String to Int Converter Using Ast.literal_eval

This function evaluates an expression node or a string consisting of a Python literal or container display.

## Python3

 `from` `ast ``import` `literal_eval`` ` `int_value ``=` `literal_eval(``"1234"``)``print``(int_value)``print``(``type``(int_value))`

Output

```1234
<class 'int'>

```

### String to Int Converter using str.isdigit()

Python isdigit() function returns a Boolean value TRUE if all the values in the input string are digits; else it returns FALSE.

## Python3

 `string ``=` `"42"``if` `string.isdigit():``    ``integer ``=` `int``(string)``    ``print``(integer)  ``# Output: 42``else``:``    ``print``(f``"{string} is not a valid integer."``)`

Output

```42

```

Note: float values are decimal values that can be used with integers for computation.