parseFloat() Function in JavaScript: Convert String to Number - JavaScript Tutorial

The parseFloat() function is a built-in JavaScript function that converts a string representation of a number into a floating-point number. It parses a string and returns a floating-point number.

Syntax:

parseFloat(string)

Parameters:

• string: The string to be parsed.

Return Value:

The parseFloat() function returns a floating-point number if the string is successfully parsed. If the string cannot be parsed as a number, it returns NaN (Not a Number).

Example:

const string1 = "123.45";
const string2 = "100";
const string3 = "abc";

const number1 = parseFloat(string1); // number1 = 123.45
const number2 = parseFloat(string2); // number2 = 100
const number3 = parseFloat(string3); // number3 = NaN

Notes:

• The parseFloat() function only parses the first part of the string that can be converted to a number. If the string contains non-numeric characters after the first numeric part, they are ignored.
• If the string starts with a non-numeric character, parseFloat() returns NaN.
• If the string is empty, parseFloat() returns NaN.