JavaScript Number parseFloat() method

Definition and usage

Number.parseFloat() The method parses the value as a string and returns the first number.

Note:

If the first character cannot be converted to a number, then returns NaN。

Leading and trailing spaces will be ignored.

Only returns the first number found.

Instance

Example 1

Number.parseFloat(10);
Number.parseFloat("10");
Number.parseFloat("10.33");
Number.parseFloat("34 45 66");
Number.parseFloat("He was 40");

Try it yourself

Example 2

Number.parseFloat("40.00");
Number.parseFloat(" 40 ");
Number.parseFloat("40 years");
Number.parseFloat("40H")
Number.parseFloat("H40");

Try it yourself

Syntax

Number.parseFloat(value)

Parameter

Parameter Description
value Required. The value to be parsed.

Return value

Type Description
Boolean value If a number is not found, returns NaN.

Browser support

Number.parseFloat() Is ECMAScript6 (ES6) feature.

All modern browsers support ES6 (JavaScript 2015):

Chrome Edge Firefox Safari Opera
Chrome Edge Firefox Safari Opera
Υποστηρίζεται Υποστηρίζεται Υποστηρίζεται Υποστηρίζεται Υποστηρίζεται

O Internet Explorer 11 (ή παλιότερη έκδοση) δεν υποστηρίζει Number.parseFloat()。