Number.parseFloat()

The Number.parseFloat() static method parses an argument and returns a floating point number. If a number cannot be parsed from the argument, it returns {{jsxref("NaN")}}.

{{InteractiveExample("JavaScript Demo: Number.parseFloat()")}}

```js interactive-example function circumference(r) { if (Number.isNaN(Number.parseFloat(r))) { return 0; } return parseFloat(r) * 2.0 * Math.PI; }

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

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

## Syntax

```js-nolint
Number.parseFloat(string)

Parameters#

• string
• : The value to parse, coerced to a string. Leading {{Glossary("whitespace")}} in this argument is ignored.

Return value#

A floating point number parsed from the given string.

Or {{jsxref("NaN")}} when the first non-whitespace character cannot be converted to a number.

Examples#

Number.parseFloat vs. parseFloat#

This method has the same functionality as the global {{jsxref("parseFloat()")}} function:

Number.parseFloat === parseFloat; // true

Its purpose is modularization of globals.

See {{jsxref("parseFloat()")}} for more detail and examples.

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#

• Polyfill of Number.parseFloat in core-js
• es-shims polyfill of Number.parseFloat
• {{jsxref("Number")}}
• {{jsxref("parseFloat()")}}