# Python - How To Convert a String to a Float Value in Python

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In programming, data is stored in variables, and these variables have certain data types. These data types include integer, floating value, string, and boolean values.

We sometimes run into a situation wherein we have to convert values of some data type to another data type. For example, converting `integer` to `float`, `integer` to `long`, `integer` to `boolean`, `string` to `boolean`, etc.

In this article, we will learn how to convert a string value to a floating value.

## Converting a String to a Float Value in Python

When converting a string to a float value, we must ensure that the string represents a number. For example, `"1"` and `"1.0"` can be converted to `1.0`, but we can not convert `"hello"` and `"python is amazing"` to a floating value.

Let us look into how to perform the conversion practically. Refer to the following Python code for this.

``print(float("1")) print(float("1.1")) print(float("0.231")) print(float("123")) print(float("0")) print(float("0.0")) print(float("+12")) print(float("10e10")) print(float("-125")) ``

Output:

``1.0 1.1 0.231 123.0 0.0 0.0 12.0 100000000000.0 -125.0 ``

Python has a `float()` function that can convert a string to a floating value. Not only a string, but we can also convert an integer to a floating value using this in-built method.

As mentioned above, we can not convert a string representing a sentence or a word to a floating value. The `float()` method will throw a `ValueError` exception for such a scenario.

The following Python code depicts this.

``print(float("hello")) ``

Output:

``Traceback (most recent call last):   File "<string>", line 1, in <module> ValueError: could not convert string to float: 'hello' ``

If we are unsure about the string values that we pass to the `float()` method, we can use `try` and `except` blocks to catch exceptions and continue with the program’s execution. Refer to the following code for this.

``strings = ["1.1", "-123.44", "+33.0000", "hello", "python", "112e34", "0"]  for s in strings:     try:         print(float(s))     except ValueError:         print("Conversion failed!") ``

Output:

``1.1 -123.44 33.0 Conversion failed! Conversion failed! 1.12e+36 0.0 ``

As we can see, the `try...except` block helped us catch exceptions for `"hello"` and `"python"`. For other elements, the algorithm ran seamlessly.