JavaScript parseFloat()

const stringDate = "23.9";

// parse the string to float value
let floatDate = parseFloat(stringDate);
console.log(floatDate)

// Output: 23.9

parseFloat() Syntax

The syntax of the parseFloat() function is:

parseFloat(string)

parseFloat() Parameters

The parseFloat() function takes in:

• string - The value to parse. If it is not a string, it is converted to one using ToString abstract operation.

Note: Leading whitespace characters are ignored.

parseFloat() Return Value

• Returns a floating-point number parsed from the given string.
• Returns NaN when the first non-whitespace character can't be converted to a number.

Example: Using parseFloat()

console.log(parseFloat("  10  ")); // 10
console.log(parseFloat("  3.14seconds")); // 3.14
console.log(parseFloat("314e-2")); // 3.14

// argument can be anything as long as it has toString or valueOf
const obj = {
  toString: () => "127.0.0.1",
};
console.log(parseFloat(obj)); // 127

console.log(parseFloat("JavaScript")); // NaN

// BigInt values lose precision
console.log(parseFloat("464546416543075614n")); // 464546416543075600

Output

10
3.14
3.14
127
NaN
464546416543075600

Recommended Reading: Javascript parseInt()