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Number.parseInt

The Number.parseInt() method parses a string argument and returns an integer of the specified radix or base.

Syntax

Number.parseInt(string,[ radix])

Parameters

string
The value to parse. If this argument is not a string, then it is converted to one using the ToString abstract operation. Leading whitespace in this argument is ignored.
radix Optional
An integer between 2 and 36 that represents the radix (the base in mathematical numeral systems) of the string. Be careful—this does not default to 10!

Return value

An integer parsed from the given string.

If the radix is smaller than 2 or bigger than 36, and the first non-whitespace character cannot be converted to a number, NaN is returned.

Polyfill

if (Number.parseInt === undefined) {
    Number.parseInt = window.parseInt
}

Examples

Number.parseInt vs parseInt

This method has the same functionality as the global parseInt() function:

Number.parseInt === parseInt // true

and is part of ECMAScript 2015 (its purpose is modularization of globals). Please see parseInt() for more detail and examples.

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
parseInt 34 12 25 No 21 9
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
parseInt ≤37 34 25 21 9 2.0
Server
Node.js
parseInt 0.12

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/parseInt