Number.parseFloat()

Baseline

20159

Number.parseFloat() NaN

function circumference(r) {
  if (Number.isNaN(Number.parseFloat(r))) {
    return 0;
  }
  return parseFloat(r) * 2.0 * Math.PI;
}

console.log(circumference("4.567abcdefgh"));
// : 28.695307297889173

console.log(circumference("abcdefgh"));
// : 0

Number.parseFloat(string)

string

string

NaN

Number.parseFloat parseFloat

parseFloat()

Number.parseFloat === parseFloat; // true

parseFloat()


ECMAScript 2027 LanguageSpecification # sec-number.parsefloat

Number.parseFloat (core-js)
es-shims Number.parseFloat
Number
parseFloat()

MDN

MDN 2025826

GitHub

Number
1. Number()
Object/Function
1. __proto__
2. constructor