JavaScript parseFloat() Method is used to accept the string and convert it into a floating-point number. If the string does not contain a numeral value or If the first character of the string is not a Number then it returns NaN i.e, not a number. It actually returns a floating-point number parsed up to that point where it encounters a character that is not a Number.
Syntax:
parseFloat(Value)
Parameters: This method accepts a single parameter.
- value: This parameter obtains a string that is converted to a floating-point number.
Return value: It returns a floating-point Number and if the first character of a string cannot be converted to a number then the function returns NaN i.e, not a number.
Below is an example of the parseFloat() method:
Example 1:
javascript
let v2 = parseFloat("3.14"); console.log('Using parseFloat("3.14") = ' + v2); |
Output:
Using parseFloat("3.14") = 3.14
Example 2:
javascript
// It ignores leading and trailing spaces. a = parseFloat(" 100 ") console.log('parseFloat(" 100 ") = ' + a); // It returns floating point Number until // it encounters Not a Number character b = parseFloat("2018@neveropen") console.log('parseFloat("2018@neveropen") = ' + b); // It returns NaN on Non numeral character c = parseFloat("neveropen@2018") console.log('parseFloat("neveropen@2018") = ' + c); d = parseFloat("3.14") console.log('parseFloat("3.14") = ' + d); // It returns only first Number it encounters e = parseFloat("22 7 2018") console.log('parseFloat("22 7 2018") = ' + e); |
Output: The parseFloat() function ignores leading and trailing spaces and returns the floating point Number of the string.
parseFloat(" 100 ") = 100
parseFloat("2018@neveropen") = 2018
parseFloat("neveropen@2018") = NaN
parseFloat("3.14") = 3.14
parseFloat("22 7 2018") = 22
Example 3: Using the isNaN() function to test whether the converted values are a valid numbers or not.
javascript
let x = parseFloat("3.14"); if (isNaN(x)) console.log("x is not a number"); else console.log("x is a number"); let y = parseFloat("neveropen"); if (isNaN(y)) console.log("y is not a number"); else console.log("y is a number"); // Difference between parseInt() and parseFloat() let v1 = parseInt("3.14"); let v2 = parseFloat("3.14"); console.log('Using parseInt("3.14") = ' + v1); console.log('Using parseFloat("3.14") = ' + v2); |
Output:
x is a number
y is not a number
Using parseInt("3.14") = 3
Using parseFloat("3.14") = 3.14
Supported Browsers:
- Google Chrome 1 and above
- Edge 12 and above
- Firefox 1 and above
- Internet Explorer 3 and above
- Safari 1 and above
- Opera 3 and above
We have a complete list of JavaScript Number constructor, properties, and methods list, to know more about the numbers please go through that article.
